Where do the best shots come from?

Some people may say that odd-year summers are a dull moment for soccer fans, but I tend to disagree. Instead of getting us sucked into the maelstrom of actuality, this period allows us take a step back and see the bigger picture of football matches. Over the course of the summer, this is what 11tegen11 will do. More depth, less actuality! After that, activity will resume as normal, strengthened by our new found knowledge…

To kick off the summer period, this piece will look at shots and identify four different strike zones on the pitch, where vastly different types of shots are being produced. This may not be all that shocking, as most of it connects with common sense of watching football games, but at the very least, it will provide a nice base for future explorations.

Basically, we could take two different approaches to identify strike zones. Either top-down, by adhering to known areas on the pitch, like the penalty box, the 6-yard box, etc. This obviously has the advantage of easy communication. But the disadvantage would be that the discriminatory power would be less, as shot quality may differ quite a bit within these classical zones.

The alternative, and the method I will use, is a bottom-up approach by using a fine grid to identify where on the pitch the biggest drop of in shot quality occurs, and then work out the best zones from there.

Here’s an Excel-produced half football pitch, split into small grids, with the conversion being printed in each grid and color marks indicating zones of high and low conversion. Conversion, in this case, is goals per shot and data covers the past two Eredivisie seasons. It’s not intended to be fully readable, but the basic point is that it allows the identification of four different strike zones.

Conversion pitch

The continuous line marks the borders of the pitch, and for reference, the penalty box. The dotted lines mark zones, where you can see a clear demarcation in shot conversion. We will use these boxes to identify four different strike zones, each with unique characteristics, as we’ll find out later.

Unsurprisingly, right in front of the goal, nearly all shots are converted into goals. I will therefore refer to this zone as Zone 1. The next most threatening part, Zone 2, covers mostly the central penalty box area, but stretches just beyond the edge of the penalty box. Then comes Zone 3, covering the wider penalty box area as well as longer distance central shots. The rest of the pitch will be Zone 4.

Pitch zones

This table shows the mean conversion rates per zone, indicating that each zone has a distinctly different conversion rate, going a factor three down as we progress down each zone. Shots from Zone 1 are rare, but due to their extremely high conversion they deserve their own group. All other zones contain a reasonably high number of shots, indicating a good distribution of shots among these zones.

Zone

Mean conversion rate

Shots

1

0.805

123

2

0.222

5435

3

0.082

4219

4

0.034

5452

These strike zones will prove a useful reference point to assess difference between teams in terms of strategy, difference between players in terms of quality and will help to explore our beautiful game more in depth.