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Holland 1 -2 Germany: The broken team…

A match that Holland needed to win in order to keep chances of qualifying to the knock-out stages of Euro 2012 in their own hands, ended in a bitter defeat. Germany had the better of the game, except maybe in the closing stages when Van Marwijk made some changes and Holland bravely, but desperately, chased an equalizer. In the end, Germany thoroughly deserved the victory, based on their tactical superiority and several key German players outperforming their Dutch counterparts.

The starting line-ups

The starting line-ups

A lot of speculation went on in the build-up to this game and most of it concerned whether Klaas-Jan Huntelaar should start ahead of Robin van Persie and whether Van der Vaart should be accommodated as deep-lying playmaker in favour of either Van Bommel or De Jong.

However, Van Marwijk opted for the same starting eleven that played against Denmark, with the exception of Joris Mathijsen who returned from injury at centre-back, at the expense of Ron Vlaar.

Germany manager Joachim Löw fielded the expected starting eleven.

 The first half

The game started out at a slow pace with both teams happy to take some time to settle in. In most matches, either one or both of the teams look to take advantage of open play turnovers to launch quick breaks, but this match was different early on. Both teams set out rather patiently, mainly aiming not to lose possession in dangerous areas, and knowing that not conceding might be the main objective early on.

But after this quiet opening phase, some interesting aspects could be seen. Holland had created a few chances when Van Persie used his excellent of the ball skills to get in behind the German defensive line, but he failed to convert his early opportunities. Germany soon adapted by dropping their defensive line a bit deeper, thereby opening up more space in midfield, which soon worked to their advantage.

Özil’s movement

Germany smartly used Mesut Özil’s lateral movement to unsettle the Dutch defense and take advantage of the large spaces in midfield with both teams’ defensive lines wary of conceding too much space in behind them.

As can be seen from the diagram below, Özil received passes both at the right and left offensive midfield area, indicating his smart lateral movement. Particularly on their right wing, Germany created numerous offensive moves, with Thomas Müller clearly dominating the struggling left-back Jetro Willems.

With Özil moving laterally, a choice had to be made in the Dutch defensive midfield zone. Nigel de Jong mostly covered Özil in his lateral runs, but this left Van Bommel on his own to cover the ground in front of the Dutch defense, where he was overloaded by Khedira and Schweinsteiger.

Broken team

The same diagram shows that Wesley Sneijder operated in his beloved left wing area, but his activity in this match was concentrated here even more than it was before. This is not to state Sneijder had a weak game, not at all, but the defensive part of his job as a central offensive midfielder was an area that Germany smartly exploited.

With Sneijder mainly staying high up the pitch and the Dutch defensive line wary of not conceding space in behind them, the ‘broken team’ problem appeared. The distances between the offensive four and the defensive six were way too large for Van Bommel to be covered, even more so with De Jong being dragged aside by Özil.

Broken wings

An area where Holland normally dominates their opponents are the wings. And both of them failed to perform here. Ibrahim Afellay had an anonymous game and failed to contribute. On the other wing, much of the credit should go to Philipp Lahm, who defended very well against his team mate Arjen Robben. Lahm, a right-footed defender who fills in at left-back for his country had the advantage of protecting against Robben’s inside runs with his stronger foot and prevented Robben from making his usual threatening runs. Germany’s excellent defensive performance also stood clear from the tackling chart (below), and from the fact that the Germans won 65% of the duels, a record high rate at European Championships since 1980.

Another reason for the disappointing wing performance was the complete lack of offensive contribution of the full-backs. Jetro Willems had his hands more than full defending Thomas Müller and Gregory van der Wiel failed to overlap and lend support to Robben.

Schweinsteiger

 The main man for Germany was Bastian Schweinsteiger. The Bayern München midfielder smartly advanced in central midfield and teaming up with Sami Khedira, he overloaded Van Bommel on occasions that Özil had already dislodged De Jong sideways. This 3v2 battle in midfield proved crucial to created the two goal scoring chances that striker Gomez showed his clinical finishing skills on.

The second half

 The second half started with Klaas-Jan Huntelaar up front, Robin van Persie in behind him, coming mainly from a left wing role with the invisible Afellay removed, and with Rafael van der Vaart introduced for Mark van Bommel. The Dutch captain was the scapegoat for the disastrous first half, both in terms of tactical developments and in terms of players underperforming. After an initial ten minutes where Germanycould and perhaps should have taken advantage of a few good opportunities, Hollandslowly fought their way back into the match.

 Around the hour mark, Van Marwijk opted to switch Van Persie and Sneijder, much like he did in the closing stages of the Denmark game. For Sneijder, who already operated in that zone, not all too much changed, but Van Persie seemed liberated in his role as a second striker, sometimes joining up high with Huntelaar, sometimes dropping deeper to escape the attention of the German centre-backs. Another notable advantage of this change was that without a nominal wide left winger, it was easier to pose threats to the German defense. Before, the German defense was sure to outnumber the Dutch centrally, with Sneijder and Afellay by and large working in the same part of the pitch. But Van Persie’s vertical movement from a deeper lying striker position posed more problems for the German defense and more options for Sneijder’s passing from a static lateral position.

The improvement brought about by this chances was evident in the Dutch goal, where an Van Persie once again showed his excellent skills in creating, and this time also finishing, his own goal scoring chance.

 Overall it didn’t prove enough for the win and in fact the best chances in the second half fell to the Germans with goal keeper Stekelenburg proving his worth on attempts by Özil and Badstuber.

In the end

In a match where both the tactical performance and the individual player performances were below-par, Holland didn’t deserve anything more than this defeat. Germany smartly exploited the distance between the Dutch front four and the defensive unit and two well-timed runs from deep by Schweinsteiger were enough for the win.

Let’s not forget that Holland are not eliminated yet, a two goal win over Portugal might still do the trick if Germany beats Denmark in their final game.

Holland 0 – 1 Denmark: Dominating chances, but losing the game

Holland dominated the game 4 to 1 in terms of chances created, but failed to convert any of them, while Denmark smartly worked their left side of the pitch to score the only goal of the game. Simon Poulsen kept overlapping on Holland’s right side and one of his runs contributed to the only goal of the game. Holland’s offense looked on song in terms of creating, but lacked in finishing.

 

Starting formations

The starting line-ups

Holland lined up in the expected double pivot variant of their well-known 4-2-3-1 formation. Nigel de Jong and Mark van Bommel formed the pair of holding midfielders to protect the back four, where Ron Vlaar filled in for the injured Joris Mathijsen. Up front, Robin van Persie had a week earlier already been announced as the starting striker and 18-year old Jetro Willems got the nod ahead of Stijn Schaars at left-back.

Denmark’s system has been described as a 4-2-1-3 by the excellent Michael Cox of Zonal Marking. Much of the build-up runs through Christian Eriksen, who is the liaison player to link balls coming from the defensive unit of six and the front three. Denmark’s front three players present an interesting mix of different roles. Striker Bendter performs a classic number nine role in holding up the ball and tries to come at the end of crosses. Those crosses mainly come from the right wing, where Rommedahl exploits his pace. Left winger Krohn-Dehli provides more of an inside winger role, which creates space for offensive left full-back Poulsen to express strong offensive qualities.

 

The first half

With a positive, high-pressing approach, Holland dominated the majority of the first half. The Dutch operated from their double pivot 4-2-3-1 system, a system that sounds more conservative than it in fact is. A high level of pressing, with the front four pressing as high as the Danish goal keeper, won a lot of early possession and the back four found a nice balance in playing a high defensive line without being overlapped.

The major area of concern for Holland was obviously the Danish left side. While most, if not all, of the pre-match attention was focused on 18-year Jetro Willems at left-back, all of the trouble this game was found at Van der Wiel’s side. Not that the Ajax player was to blame here, Denmark smartly worked that side to overload Van der Wiel.

Danish left-back Simon Poulsen, who plays for Dutch side AZ, on a contract that runs out this summer, overlapped Arjen Robben, who consistently failed to track back. Instead, Van Marwijk seemed to have opted for one the holding midfielders to assist Van der Wiel in dealing with this threat. On top of winger Krohn-Dehli and full-back Poulsen, also playmaker Christian Eriksen frequently drifted into this area, turning it into Danish playground at times.

Still, despite this issue, Holland clearly dominated the game, and the first half stats of 16 shots to 5 told quite a story. However, by that time, on of Denmark’s left wing attacks had resulted in the opening goal. A second remarkable half-time stat, which also continued over the second half, was both teams completing over 80% of their passes, with Holland even over 90%. This might well be a tell-tale of the amount of space on the pitch, with neither side retreating, but pressuring forward instead.

 

The second half

With a clear dominance in the amount of chances created, there wasn’t much incentive for Van Marwijk to make any radical changes yet. And indeed, with 6 shots in the first 8 minutes of the second half, things seemingly went the right way for Holland. Apart from converting chances that is. The Danes, meanwhile, kept on working the left wing, but their crosses lacked quality in the second half, partly due to less bodies sent forward now.

Most of Holland’s dynamic offensive performance was run by an excellent performance of Wesley Sneijder. The Inter midfielder received 79 passes, which made him stand head and shoulders above his teams mates in this regard. He frequently drifted out to the left wing to make short combinations with Afellay and this pair completed 35 passes between them, way more than any other combination of players out on the pitch. Sneijder’s tendency to drift to the left also opened up space for Arjen Robben to make his characteristic, some would say predictable, inside runs. However, the Bayern player lacked a quality end-product, only shooting from long range and losing four of his five take-ons.

 

Substitutions

With the energy visibly drained in the warm circumstances, the need for substitutions was clear. Van Marwijk had a wealth of options available, but the fact that chances kept being created indicated that no switch in approach was indicated. Van Marwijk, confirming this in his post-match interview, opted to introduce Huntelaar for the drained Afellay. This moved Van Persie, who by then uncharacteristically had missed a series of good chances, into the hole behind the striker. Simultaneously, Van der Vaart was introduced in midfield to replace De Jong and Sneijder moved out wide left.

However, the goal would not come. Huntelaar’s chip on a delicious Sneijder through-ball was saved by Andersen and several long shots failed to find the target. With the final whistle near, Holland also had a penalty shout turned down, but these kind of things don’t make you lose a match. Failing to convert any of the 32 chances created does.

This type of match also signifies the difference between league and tournament football. Should a team start its 30-something campaign with a 0-1 loss and a 32-8 dominance in shots, they would look good for a title challenge as conversion will return to average level in the long run. In short competitions like these tournaments, however, there is no long run and the rare event of failing to convert 32 chances, while conceding a goal in one of 8 chances conceded, means elimination is nearby.

 

In the end

Overall Holland created 32 goal scoring chances, but failed to score. In tactical terms, Denmark made excellent use of the fact that Holland’s wingers, most notably Robben, failed to track back. This brought them the attack that produced the goal, but a series of dangerous crosses too. On the other hand, this handed Robben more freedom to make his runs, but the winger suffered from a lack of end-product.

The fact that Holland created this many chances means they did most of the things right and in a low scoring game upsets are always going to happen. And it is in short competitions like these tournaments that these upsets have drastic consequences. But this does not mean the approach has been wrong, or choices would have needed to be different. Van Marwijk and his team adopted an approach that would have won the game in most occasions, just not today…

Euro 2012 Tactical Preview: Double Pivot with RVP up top!

With less than a week until the kick-off of the next major international tournament, it is time to consider some tactical issues going into Euro 2012. And 11tegen11 is not the only one to do so. During the build-up to next week’s kick-off, for the Dutch on Saturday against Denmark, tactical issues are being discussed all around.

It is safe to say that around these major tournaments no Dutchman seems short of a powerfully formulated opinion on how the national team should play and it is striking to note how many of those take a different view compared to what the manager prefers. Thereby taking the easiest spot.

Should Holland not be crowned Champions of Europe in a few weeks time, things will be considered to have gone wrong. Fans having taken that easy spot of disagreeing with the manager will console themselves with their moral victory of having had a different view on how the team should have played and do seldomly concern themselves with the fact that the performance under their tactical preferences might have been the same, or even worse. Fitting with this excellent depiction by @Zone_14 on the Beyond the Pitch website, summarizing the Dutch football fans’ mentality as having a massive inferiority complex, wrapped in an ever great superiority complex.

That being said, this preview will now focus on the two most debated topics regarding the Dutch national team: which version of the 4-2-3-1 formation to play and which striker to use. Minor issues by now are the left wing area, where Ibrahim Afellay earned his starting spot over Dirk Kuyt, who played more matches than any other player under Van Marwijk, with a series of bright and energetic performances, showing that the Barcelona winger has returned to fitness in time, after injuring his cruciate ligaments early this season. Furthermore, the only position that has not been clearly settled yet is at left-back, where both Stijn Schaars and Jetro Willems compete for the starting spot. Young Willems barely has 1500 minutes of Eredivisie experience for PSV under his belt, but offers offensive qualities that seem more limited with Schaars playing. The Sporting Portugal player, however, offers more experience and this may give him the edge here.

 

The starting XI for Euro 2012

The formation

Obviously, Holland will operate in a 4-2-3-1 formation. They’ve done so for all of the past years and to no shortage of success. As has been extensively described earlier, Van Marwijk generally uses two different variants of that formation. The first one, used against comparable or superior level opposition, fields two genuine holding midfielders and will accordingly be termed The ‘ Double Pivot’ version. This was also the preferred version throughout the nearly successful 2010 World Cup campaign.

The second variant field one holding midfield and pairs him with a deep-lying playmaker, as Van Marwijk has preferred against defensive sides of inferior quality. This version will be termed the ‘ Deep-Lying Playmaker’ version and was used for most of the Euro 2012 qualifying matches.

It is safe to say that Holland will use the Double Pivot formation during Euro 2012. However, this still remains an area where the majority of the fans disagree with Van Marwijk. There is a loud voice demanding the creativity of Van der Vaart to be installed, rather than the defensive solidity of Nigel de Jong. A frequently heard phrase which is used here is that this “ brings more football to the team”, as if defending is not part of playing football…

 

Comparing the Double Pivot and the Deep-Lying Playmaker

When we arbitrarily consider all matches that Holland has played since the start of the 2010 World Cup, we find 29 matches, of which two can be excluded from further analysis. Against Ukraine they fielded a B-side in what most resembled a 4-3-3 formation, against Bayern Munich they did not play another country. Of the World Cup final we will consider the result after 90 minutes.

The Double Pivot was used in 20 matches and produced 2.39 points per game, while the Deep-Lying Playmaker was used in the remaining 7 matches to produce a magnificent 2.71 points per game.

However, this analysis would not be complete without considering the fact that the DP was used against significantly higher rated opponents compared to the DLP. The average FIFA ranking of the DP opponents is around the level of the Czech Republic, while the average DLP opponents ranked around the level of Hungary.

 

The striker

This is another example of the manager’s favorite versus the fans’ favorite. With the top scorers of both the English Premier League and the Bundesliga to choose from, some have termed this a luxury problem. Klaas-Jan Huntelaar has won over lots of support among the fans with his magnificent goal scoring record in the Euro 2012 qualifying campaign, while Robin van Persie’s goal draught at the World Cup helped Huntelaar’s case further.

Before we’ll go into the numbers here, consider the following. Would you prefer Holland to win the tournament, or the striker to score goals? Right, and that is exactly what is wrong with looking at the outcome side of things (goals, assists) on an individual basis in a team sport. There seems to be growing trend among comparable sports, like basketball and ice hockey, to look at team outcomes with particular individual players playing. For a number of reason, however, this methodology is difficult to translate directly to football.

The same set of matches that we used above shows us that KJH scored 14 goals in the 13 matches that he started as a striker, while RVP scored only 5 in 14 games starting as a striker. Ironically, RVP also scored five goals playing as a left winger while KJH started up top. Again, KJH played inferior opposition with the average FIFA ranking corresponding with Macedonia, while RVP’s opponents averaged the strength of Switzerland or Ireland.

Things are more relevant at team level, however, and with 2.57 points per game with RVP starting as a striker he certainly has the edge over KJH’s 2.15 points per game.

 

Which striker to play?

Combining the DP-DLP and KJH-RVP choices brings about the most interesting oberservations. It turns out that Holland has a record of 9-2-0 using the Double Pivot with Robin van Persie up top. Compare this with 5-1-3 with the DP and KJH up top…

 

In the end

It seems the Double Pivot with RVP up top brings the best results against teams of comparable or superior quality, and that’s exactly the type of teams Holland will meet in Poland and Ukraine over the coming weeks.

And it makes sense too. Installing a second defensive midfielder, in casu Nigel de Jong, rather than a more creative deep-lying playmaker, in casu Van der Vaart, provides more cover for the defense, by all means the weakest link in the chain that is the Dutch team. De Jong may be most known for his physical presence and tackling, but his pass completion percentage over the past season, in much the same role as he’ll play in Euro 2012, was a staggering 94%. In other words, he’ll give away less than one in 16 balls. An important part of diminishing the pressure on the defense behind him…

An important difference between RVP and KJH is the striker mobility. In his role at the national team, RVP tends to drift from the striker area, thereby opening up space for the wingers and offensive midfielder to take advantage of. Huntelaar may be the better finisher, but it’s the overall team performance that counts in the end.

Why taking up the PSV or Groningen vacancy is a good idea, and the Heerenveen job is not…

With the regular matches of the 2011-12 Eredivisie season over, and only the promotion/relegation play-offs and the Europa League qualifier play-offs still in contention, several teams are either appointing or releasing managers right now. Groningen fired Pieter Huistra, whose contract they renewed as recently as during the past winter break. Veteran manager Dick Advocaat took up the PSV job, after Philip Cocu indeed proved to be just an interim solution for the job vacancy after Rutten quit. Ron Jans announced his departure from Heerenveen earlier this season, with Marco van Basten returning to a managing job here.

This post will outline why the first two jobs, at Groningen and PSV, are excellent opportunities, while the Heerenveen job is a pitfall. The same parameter that was introduced recently to differentiate between sustainable and unsustainable performance at club level, PDO, is used again here. For a full description of PDO, read the introductory post, written a few weeks ago.

 

PDO from season to season

The key concept for this post is the fact that PDO has an enormous influence on a team’s performance throughout a single match and also over the course of a single season. This becomes clear when we look at two teams with very different PDO’s in the 2010-11 and the 2011-12 season. However, PDO fluctuates a lot from match to match and from season to season, as has been demonstrated before by James Grayson on his excellent blog in a much larger data set than the two Eredivisie season that I have available here.

By now it’s very much clear that last year’s over-performers, Groningen had a terrible run this year, leading to the sacking of their manager, Pieter Huistra. Groningen’s PDO dropped dramatically, coming from 1045 and 2nd best in the league and finishing the 2011-12 season at a dramatic PDO of 936, the worst in the league at some distance. The best example of the reverse trend is Feyenoord. Their PDO last year was 988, not dramatic, but still indicating that the team had more quality than their 10th place in the 2010-11 league table represented. Feyenoord’s 2011-12 PDO is 49 points higher at 1037 and they finished the season in a much improved 2nd spot in the table.

PDO data from all clubs over the past two seasons are presented in the next table. Note that this table only contains 17 clubs, as there was one promotion/relegation in between these seasons.

PDO

2010-11 2011-12
Ajax

1031

1026

AZ Alkmaar

995

1026

Den Haag

1050

976

Excelsior

977

968

Feyenoord

988

1037

Graafschap

974

963

Groningen

1045

936

Heerenveen

1019

1057

Heracles

997

977

NAC Breda

1018

996

Nijmegen

1027

980

PSV Eindhoven

1019

978

Roda

1042

1019

Twente

1014

1038

Utrecht

1013

1010

Vitesse

970

1005

VVV Venlo

935

982

 

A quick mind will have noted that there is no correlation between both seasons. In other words, a high (or low) PDO in one year indicated nothing about the level of PDO in the next year. This is well illustrated in the next graph, depicting both seasons in a scatter plot. Note the flat trend line with a near-zero correlation coefficient.

 

 Now, what does this mean? Coming off a low-PDO season, things can only get better at clubs like PSV and Groningen, while teams like Feyenoord, Twente and particularly Heerenveen, who come off extremely positive PDO’s are in for a disappointing year.

Good luck, Marco!

 

Data: Infostrada Sports

The ‘Lokhoff’ effect & The ‘McClaren’ non-effect

The previous post introduced the concept of PDO, a statistic that was originally introduced in the NHL a few years back, to determine which share of a team’s performance can be attributed to non-sustainable performances (‘luck’) and which share to sustainable performances (‘skill’). Since it’s an important concept in order to understand the following graphs, let me provide a short summary of PDO. A more detailed explanation can be found in the previous post, where lots of links are provided to suggest further reading on the topic.

In short, PDO combines a team’s shooting percentage (Sh% = the fraction of goal scoring attempts created that is scored)  and a their saves percentage (Sv% =  the fraction of goal scoring attempts conceded that is scored). It’s as simple as that.

PDO = 1000 * (Sh% + Sv%)

Does a high shooting or saves percentage gives your team a good chance of winning the match at hand? Certainly! But does it provide a solid base to build your future on? No, definitely not.

The single thing  to get your head around in order to get to grips with the concept is that what constitutes Sh% and Sv% in future matches is for almost 90% random and only just over 10% correlated to the previous performance. Again, see previous post

Now, what can we rely on then? Of all representatives of a good performance, parameters like points won, goals scored, shots taken , etc., the best correlation is found for the total shots ratio, or the fraction of shots in a particular match that is taken by your team. Future performances show over 60% correlation with historical data, making this the best predictor for future performance…

 

The ‘Lokhoff’ effect

Now, with the theoretic part out of the way, let’s get to the fun part. The graph below is a simple illustration of VVV’s points per game (PPG) over the course of the 2011/12 Eredivisie season.The graph shows the cumulative average points per game, restarting when the new manager was appointed.

Managed by Belgian Glen de Boeck, VVV found themselves struggling to avoid relegation and finished the first half of the season on the 17th place in the table, five points behind the safety of the 15th spot. De Boeck was fired, and experienced manager Ton Lokhoff was installed around Christmas time. With the season now over, VVV finished in 16th place and came one point short to avoid the relegation play-offs…

Points per game (PPG) under De Boeck (first half of season) and Lokhoff (second half of season)

In terms of PPG, the installment of Lokhoff certainly coincided with an improvement. During the first half of the season, managed by De Boeck, VVV obtained 0.59 PPG, never topping the 0.65 mark after more than a few games had been played. Under Lokhoff, however, VVV lived the dream and started out brilliantly, before settling down to finish at 1.24 PPG. With that rate, they would have finished a full season at 42 points, enough for a comfortable 12th place. Note that the graph, as well as the next ones, use a cumulative average over the course of the season, and that this cumulative average is reset upon the installment of the new manager. In other words, the number shown at match day five is the average PPG over the first five matches and the average shown at match day fifteen is the average over the first fifteen matches.

 

Luck or skill?

The key question now is, was De Boeck unlucky when managing VVV, or did Lokhoff really improve the performance. In order to answer that question, we can look at the PDO and the Total Shots Rate (TSR) for both parts of the season.

VVV's luck (PDO) and skill (TSR) in the first and second half of the season

In this graph it is well illustrated that the season started out with the PDO developing pretty close to the 1000 mark, which indicates a neutral amount of luck came VVV’s way. Later on VVV rode an unlucky series, with the PDO slowly tailing off, even as far as to finish the first half of the season at a dramatically low 970. The TSR, meanwhile, reflecting the sustainable level of performance, was ever increasing throughout the season and finished at 0.333, not high in absolute terms, but steadily rising as a sign that De Boeck got his team improving as he went along. The combination of an improving performance and the dropping PDO resulted in the rather flat PPG.

Under Lokhoff, VVV started brilliantly in terms of their TSR, but as more matches were played this extreme level of performance proved unsustainable, but they still showed an improvement over De Boeck’s 0.333 and finished at 0.400. However, following the trend in TSR under De Boeck, VVV might well have finished the season around the 0.400 level too!

A short bump in PDO helped VVV to their excellent start under Lokhoff. All in all, they finished the second part of the season with a PDO of 1010, mostly due to a rise in the final three matches, thereby compensating for the decreasing TSR, overall resulting in an upkick in PPG in the final three matches.

 

The ‘McClaren’ non-effect

VVV showed an remarkably different pattern of performance under both managers, as indicated by the rising TSR under De Boeck and the falling, though higher, TSR under Lokhoff. Twente’s story is quite a different one. Their season started out brilliantly, with the team winning their first four matches and eventually settling around the 2.0 PPG mark. During the winter break, manager Co Adriaanse was fired, not so much because of a lack of result, but because of communication issues with the players as the story ran. The return of manager Steve McClaren brought an excellent start, but soon the team’s performance faded and the season ended dramatically as McClaren finished way below expectations at 1.59 PPG.

Twente's points per game (PPG) curve under Adriaanse (left) and McClaren (right)

Let’s study Twente’s PDO and TSR to look for an explanation as to why McClaren started well, but faded so dramatically.

Under Adriaanse, Twente’s TSR was relatively stable, as was their PDO. However, their extremely high level of a PDO of 1068 over the first half of the season always seemed unsustainable. Twente’s high level of PDO held on almost during the entire season, even increased during McClaren’s first 8 games, but finally came down. Some awfully back luck saw McClaren’s team return to average in order to finish the second half of the season with an average PDO of 992.

Twente's luck (PDO) and skill (TSR) in the first and the second half of the season

 

In the end

Simple curves, yet interesting observations. VVV manager Glen de Boeck was fired after running into some bad luck, with the team’s PDO falling dramatically. Despite his steadily increasing TSR, which indicates an improving performance, this drop in PDO prevented his team from getting the points that their improving performance deserved. De Boeck’s successor Lokhoff did improve the team initially, but his TSR is dropping ever more, indicating that that initial bump in improvement will not hold for the long run. Assisted by a run of better luck he got off to a flying start.

At Twente, Adriaanse got the team performing at a rather constant level, around a TSR of 0.6. However, Twente’s PDO level over 1060 was never going to hold in the long run. Under McClaren, Twente’s performance initially dipped, but improved near the end to finish the season at the same level as under Adriaanse. However, a return to average PDO levels made the performance drop dramatically, a development that was just waiting to happen.

Winning matches, is it luck or skill?

One of the most attractive parts of football is obviously that it is so unpredictable.  Who would want to watch full matches when the outcome is known before the kick-off? In the low-scoring game that football is, predicting winners is difficult. Yet, at the same time, some teams are genuinely better than others, they win more matches and are rightly provided better pre-match odds of winning. The fact that they don’t win all of the time proves that there is an element of luck involved.

This post will try to separate the two entities that determine who wins a football match: luck and skill. And in order to do so, we must agree on the difference between these two qualities. The key concept that makes a lucky team different from a skilled team is sustainability. Any team would be able to pull off a miraculously good performance in a single match, but to string good results together requires more than luck, it requires a certain level of skill. The better the result and the longer the string of good results required, the higher the level of skill needed.

So far, so good. But which factors represent team performance and are sustainable? Goals scored? Goal difference? Points won? Shots taken?

 

Shots, conversion and saves

The brilliant James Grayson looked into this matter and used a large data set, containing 702 back-to-back seasons, to assess the season-to-season correlation between offensive and defensive parameters that indicate a level of performance (goals, shots, shot conversion, etc.). This research raised more than a few interesting points, most of which are inferred from ice hockey analysis, where the following statistical measures are much more common.

First, the variable that showed the best correlation between one season and the next proved to be the total shots ratio, or TSR. So the best predictor for future performance seems to be the fraction of shots within a match that a team takes. This shows even more correlation between seasons than the number of points obtained by a team. Please check James’ Blog, where he explains this very well, and in more detail.

Secondly, two variables that are very important in deciding which team wins a particular game, both the shot conversion (what fraction of shots ends up in goal) and the saves fraction (what fraction of shots conceded does not end up in goal), show little or no correlation going from season to season. And this deserves some explanation.

 

Regression to the mean

It seems that the fraction of shots converted, or shooting percentage (Sh%), and the fraction of shots saved, or saves percentage (Sv%), are more influenced by luck than by skill, and much more so. This is shown with the introduction of the concept of ‘regression to the mean’. What this important principle means is that any outlying performance over a short stretch of games will tend to move towards the average for that parameter. James explains this concept very well on his blog, and Wikipedia serves those wanting the most detailed of explanations.

So, if a team shows an excellent Sh% over a season of games, think Heerenveen’s 16.7% shot conversion, or an excellent Sv%, like Vitesse’s 9.0%, this shows an unsustainable performance. Next season, Heerenveen is more than likely to suffer from a severe drop in Sh% and Vitesse to suffer from a drop in Sv%, based on this principle.

 

PDO

In ice hockey analysis, both Sh% and Sv% have been combined into a single stat, called PDO. Ice hockey stats have the nasty habit of being named after their ‘inventor’, rather than after what they measure and the term ‘PDO’ has been launched by Brian King, whose internet alias happened to be PDO.

PDO = 1000 (Sh% + Sv%)

That’s all. Simple as that, a better shooting percentage and a better saves percentage gives you a higher PDO. Most commonly it’s multiplied by 1000 to get rid of the small numbers, but that’s just convenience. Since one team’s Sv% rises when another team’s Sh% drops, the average PDO over a match, or a league, will always be 1000.

The key concept, as explained above, is that a high PDO is simply not sustainable and a low PDO will rise with more matches played. It allows an easy assessment of how much of a team’s performance is due to skill and how much to luck.

 

Counter-intuitive

Of course, it seems counter-intuitive to assume that individual goalkeeping skills don’t vary from team to team, but in James’ dataset of 702 back-to-back seasons, the Sv% from one season and the next showed a correlation of just 0.098. Click on that link for a nice graph!

Regarding shot conversion (Sh%), more or less the same holds true. The R2 value is only 0.150, indicating that Sh% regresses to the mean by over 60%, or in other words, that luck is a factor 1.5 more important than skill when it comes to converting chances. This fits well with an article by the excellent Mark Taylor, who used Arsenal’s 2011/12 season to show that shot conversion is neatly correlated with the match situation. In other words, if Arsenal are chasing games, their Sh% is almost half the rate that is it when they lead comfortably. Match situation may be more important than the skill of the player pulling the trigger, with the obvious caveat being that better teams (higher TSR) take more shots from leading positions and achieve a higher Sh%.

For the total shots ratio, things are different than for Sh% and Sv%. The TSR from one season to the next shows less than 13% regression to the mean, indicating skill dominates luck a factor 6 here.

 

Conclusion

So in conclusion, the short term performance of teams that we are used to study, and a season of 30-something matches is definitely short term in a sport as low scoring as football, leads analyists to focus on luck, rather than skill. Using the simple concept of the PDO (thank you, ice hockey analysts!) allows to separate (un)lucky teams from (un)skilled teams, while the total shots ratio (TSR) is the best representation of a team’s skill.

To round off this post, here’s a table of the 2011/12 Eredivisie teams and their respective PDO’s, Sh%, Sv% and TSR.

PDO TSR Sh% Sv%
Heerenveen 1057 0.474 0.167 0.890
Twente 1038 0.587 0.152 0.887
Feyenoord 1037 0.578 0.131 0.906
Ajax 1026 0.678 0.144 0.882
AZ Alkmaar 1026 0.586 0.121 0.905
Roda 1019 0.414 0.154 0.865
Utrecht 1010 0.456 0.122 0.888
Vitesse 1005 0.528 0.095 0.910
NAC Breda 996 0.457 0.093 0.903
VVV Venlo 982 0.369 0.106 0.876
Nijmegen 980 0.528 0.087 0.893
Waalwijk 980 0.498 0.098 0.882
PSV Eindhoven 978 0.680 0.134 0.844
Heracles 977 0.506 0.112 0.865
Den Haag 976 0.410 0.101 0.875
Excelsior 968 0.344 0.078 0.890
Graafschap 963 0.380 0.093 0.870
Groningen 936 0.545 0.085 0.851

 

Data for this table has been provided by Infostrada Sports.

Twente 1 – 2 Ajax: A major step towards the Eredivisie title for Ajax

Before the start of the present Eredivisie season, this match may have been heralded as a potential title decider, given the fact that both teams battled it out last year in both a title decider on the final match day and the Dutch Cup final. But given Ajax’ comfortable six points lead going into this match, the present match was more about the race for second place. Infostrada Sports’ Euroclubindex rated Ajax’ chances of winning the title before this match over 99%, giving Twente only an outside chance of winning the title of 0.2%.

There’s more to these two clubs than their past season rivalry though… Ajax’ passing midfielder Theo Janssen won the Eredivisie ‘Player of the Year’ 2010/11 honours in a Twente shirt and red-hot striker Luuk de Jong meets his older brother Siem as both spearhead their teams’ respective strike forces!

 

Twente’s 4-3-3

The starting line-ups

Despite Twente’s managerial change, halfway through this season, results haven’t picked up in the second half of the season. Guided by Co Adriaanse, they won 1.94 points per game, while the PPG under McClaren was 1.93 before the start of this game. Though unchanged in terms of PPG, Twente under McClaren scored less (2.36 goals per game vs 2.53) and conceded more (1.29 vs 1.06) compared to Adriaanse. This might indicate  a drop in results over the long run…

In tactical terms, Twente takes a more cautious approach, the whole ‘Chadli as a central playmaker’ experiment has ended prematurely and target man Mark Janko has even left the club. In Twente’s previous match, McClaren left Chadli out of the starting XI, but the Belgian managed to provide the game winning goal in the dying seconds, coming off the bench. This time, Chadli started from the beginning.

 

Ajax’ 4-3-3

The rise of Frank de Boer’s Ajax in the second half of the season has been more than impressive. While winning ‘only’ 1.94 PPG in the first half of the season, their second half has been truly outstanding, with 2.43 PPG before this match at Twente. While their goals scoring rate has only marginally contributed to this improvement (2.71 vs 2.86 goals per game), it’s their goals per game conceded (1.35 vs 0.79) that has made the difference. Ajax’ first half of the season has been characterized by an unfamiliar low GK saves percentage, but their second half of the season has marked the expected ‘regression to the mean’ phenomenon.

In tactical terms, De Boer has shown to stay true to his possession-based 4-3-3 system and recently important players like Boerrigter and Van der Wiel have returned to action.

 

The first half

The game started out with a comfortable control of possession by Ajax. Twente did try to take a leaf out of Feyenoord’s book, judging by the way they attempted to pressure Ajax early on, but they never really got their pressure game going. In possession, Ajax positioned their full-backs rather high up the pitch, with Van der Wiel more prominently involved than Blind today. Defending midfielder Anita dropped deep between, or even beyond the level of both centre-backs, who spread wide across the pitch.

This set-up allowed Ajax’ midfielders to make intricate passing triangles and, contrasting with the Feyenoord game, where their back line was more narrow, they comfortably avoided Twente’s pressure. In order to exert their pressure, Twente striker Luuk de Jong was assisted by midfielder Willem Janssen, who tried to track Anita into his deep position. This depleted Twente’s midfield population and proved a crucial part of their problems in this match.

 

Van der Wiel

Other problems for Twente were found on their left wing. Ajax right winger Ismael Aisatti played a nice inside winger role, and posed a decision making problem for his marker Tiendalli. Either Tiendalli would track Aisatti and leave space for Van der Wiel to make his impressive overlapping runs, or he would stay wide, leaving Aisatti to the spare centre back. But this alternative solution would allow Ajax to outnumber Twente in central midfield, given Willem Janssen’s previously described dislocation.

All in all, Ajax generally proved comfortable in possession and apart from an incidental good dribble by Ola John, who hit the post with his shot, the best chances were created by Ajax.

In a role reminiscent of his idol Dani Alves, Gregory van der Wiel featured prominently in Ajax’ best chances. His overlapping runs made excellent use of the space created by Aisatti and the relatively high position of Twente’s back line, which was needed for their pressing.  For Ajax’ 28th minute opening goal he shook off Ola John on a delicate Alderweireld through ball and rounded Mihaylov, who gently fouled him. Against his old club, Theo Janssen only just converted the penalty to give Ajax the lead.

 

The second half

Steve McClaren obviously felt the need for change, making a half-time substitution as he removed Willem Janssen for Wesley Verhoek, shifting Nacer Chadli back into central midfield, with the obvious intention to get the Belgian playmaker more involved. On top of that, the introduction of Verhoek should give Twente more width in search of the equalizing goal.

Initially, Twente gained more ground, proved able to stroke more passes together, but they didn’t solve their midfield problem. Ajax wasn’t afraid to drop deep, even in possession, and the probing runs of Van der Wiel seemed to make Twente hesitant to advance their defensive line all too far forward.  The stretched midfield allowed Ajax more advantage then it did to Twente, given Ajax’ excellent passing triangles and their numerical advantage with Aisatti’s tricky inside winger role.

 

Two more goals

In spite of their tactical worries, Twente did find the equalizer in the 71st minute. Leroy Fer hammered the ball home after Ajax failed to adequately clear a corner kick that crowned a series of Twente crosses with even centre-back Douglas involved, making a dangerous bicycle kick attempt from close range.

Twente’s advantage was short-lived though, as another one of those overlapping runs by Gregory van der Wiel allowed him to get at the end of a cross by substitute left winger Ebecilio. Van der Wiel neatly curled the ball into the top corner with his left foot, thereby winning the match for his team and ending any speculation as to who would win the MotM award today.

 

In the end

A convincing performance by an Ajax side that has practically secured the Eredivisie title by now. Twente proved unable to deal with the technical and positional skills in possession and, needing a win in their search for second place, refrained from letting Ajax enjoy possession in harmless areas. In contrast, Twente allowed Willem Janssen to pressure very high up the pitch, and fell into the midfield trap that consisted of Aisatti’s inside winger role. Van der Wiel’s overlapping runs won the game today…

Shooting stars of the Eredivisie

Only six matches remain in the 2011/12 Eredivisie and the title race is closer than ever. No less than six teams are still in contention for the title, being separated by only four points. At the bottom of the table, VVV has made an impressive come-back, to seriously threaten ADO and NAC for survival.

With the league entering its final stages,  this post will dive into the summarized offensive and defensive performances, looking to identify which teams have both their offensive and defensive performances in order for the most important matches of the year.

 

Offense

Let’s first look at the offensive performances. The graphs below depicts the teams according to the amount of shots created per game and the conversion rate of those shots. The ‘shooting star-like’ appearance comes from the fact that the performances over the first half of the season (17 matches) have been separated from  the performances in matches after the winter break. Hover over the start- and end-points of the lines to find out the actual values for different teams. Links to high resolution downloads can be found here for the offensive graph and here for the defensive graph.

 

The upper right hand corner is the area where teams with both a high number of shots and a high conversion rate will be found. It is clear that Ajax has had the best offense at present, while their short line indicates a constant performance over the season. Twente’s offense also comes in quite good, with less shots than Ajax, but a superior conversion rate.

To round off the title pretenders, Heerenveen also shows a constant performances and a high conversion rate with an above average number of shots, while Feyenoord have made an interesting shift across the map. Their first half of the season seemed to depend on shot creation, while the second half is focused on conversion. The fact the they moved in a practically diagonal direction indicates that the decline in number of shots was compensated by an improved conversion and vice versa.
PSV moves in an alarming direction, with a decrease in both number of shots and conversion, while AZ loses half a shot per game and 3% conversion.

Other remarkable shifts are to be seen at VVV, where Ton Lokhoff took over during the winter break. VVV has produced over 3 shots per game more, with a comparable conversion. An even sharper decline than at PSV is shown by Groningen, who’ve shown a dramatic decrease in both shots and conversion, to find themselves among the relegation candidates in offensive terms.
A final mention goes out to Vitesse. The only foreign owned team in Holland slipped up in terms of conversion, losing 4% there, but completely made up for it in terms of shot creation, moving from 12.3 to 17.5 per game.

 

Defense

The same graph can be created for defensive performances, this time showing the amount of shots conceded and the conversion rate allowed. In this graph, the lower left hand corner shows the best defense, while the upper right hand corner indicates serious defensive problems.

 

The eye-catching outlier here is PSV, whose dramatic conversion rate allowed of 0.196 reflects their performances in the games against Twente (2-6 loss at home with 8 shots conceded) and NAC (3-1 loss away with 7 shots conceded). Despite conceding the third lowest number of shots, this extreme conversion rate ranks their defensive performance over the second half of the season among relegation favorite Excelsior and out-of-form Groningen.

Remarkably, one of the best defensive performances has been turned in by promoted team RKC, who combine an excellent amount of shots allowed per game with a superbly low conversion rate allowed. Given their mediocre offensive record, this stunning improve in defense has been the base for their rise from 13th at the winter break to a solid ninth place with six matches to go.

Jan Wouters’ effect on Utrecht, where he took over in October, is shown with a significant improve in defense, coming at the price of a slightly decreased offensive performance. Most relegation threatened teams have improved their defensive record, with less shots conceded per game and less conversion allowed for all three of ADO, VVV and Excelsior. However, at De Graafschap the number of shots allowed has gone up.

In our half-season review, looking at the same parameters, we’ve mentioned N.E.C. as a team to watch for the second half of the season, and Alex Pastoor’s team hasn’t failed to live up to these expectations. N.E.C. has developed the best defense over the past eleven Eredivisie matches.

 

The title contenders

With only six matches to go, more value may be attributed to the performances in the past eleven matches than to the performances in first half of the season. Combining offensive and defensive performances should lead to the conclusion that Ajax seems the hot favorite to win the Eredivisie title. Heerenveen surges recently due to their improvement in the number of shots conceded. Twente is slowly slipping up in defensive terms, while Feyenoord have moved in the opposite direction. Both teams’ offensive performance seems quite constant.

PSV moves in the wrong direction both in offensive and defensive terms making their title bid more dependent on their excellent first half of the season than on their present form. Finally AZ, until recently the league leaders, but by now trailing Ajax by a point. Their offensive efficiency has let them down recently, while their defense remains on par with title rivals Ajax, AZ and Feyenoord.

This post has been created with data provided by Infostrada Sports and it has been inspired by the work of Ben Mayhew at the excellent experimental 3-6-1 website, follow him at Twitter @experimental361.