This is the sixth article in a series of articles and videos in the Where Goals Come From project from Jamon Moore and Carl Carpenter.

Data providers and analysts have long talked about successful passing “into the box” and shots that come from it, however, until now, we are not aware of a framework for providing context of how to separate “good, better, and best” of these situations other than location as identified by Expected Goals (xG), particularly one that can be used at all levels of a football club. In our estimation, this does not make the information very actionable for players. Expected Goals on their own do not provide a way of telling us the situation that created a shot.

As we are demonstrating in these “Where Goals Come From” articles, situational context matters a great deal. It’s not just the type of pass, but details such as the direction of the pass, the speed of play, the number of defenders between the ball and goal, the height of the pass, the quality of the reception (first touch), the location of the goalkeeper, and much more.

Some of these things are detectable by current data sets, and thereby included in Expected Goals models, but some are not. Boiling that down to a single decimal or percentage value for a shot alone usually loses the context that is most useful for actionable analysis, thereby creating a disconnect between the executive side, the coaching side, and the analyst side about what creates success. Ninety-nine percent of shot charts show only the shot location, not where the pass that created the shot came from.

The 18 zones of the soccer pitch

I’ve written about the 18 zones of the pitch before on this site, and many coaches and analysts understand the importance of Zone 14 and Zone 17. Zone 17 is where 82% of the goals come from given its location as the central area of the 18-yard box. An explainer can be found in the graphic below.

There are many times of zonal configurations out there, and this is not to say one is better than the other. However, when coaches talk about “putting (dangerous) balls into the box”, they pretty much mean Zone 17.

So analyzing the effectiveness of various types of key passes, and which ones work the best for both entry into Zone 17 and the ability to convert them into a shot at a minimum and, ideally, a goal, is a very important task if we want to really understand where goals come from. As the graphic above indicates, 82% of goals from open play, corners, and set pieces come from shots in Zone 17.

Conversion rates of goals based on key pass type

We can look at all the various zones and which types of key passes result in goals from each zone and how often a goal is scored from a shot in that zone.

Key pass conversion rates by zone and opportunity type. The darker the zone the greater the sample size.

This visualization shows the simple shot conversion rates for each of our key pass types from our third article in the series. Green represents Progressive Pass types, blue Basic pass types, and purple Set Piece Pass types from our five goal categories in our first article in the series.

Progressive key passes score the most goals at a rate of 20%. Through balls and Cutbacks are more efficient but less frequent. Crosses again don’t seem too bad at 14% but are scored at a similar rate as Normal passes.

In order to figure out how to use Zone 17 to our advantage, we need to determine what are the most efficient key passes and from which locations. To do this, we need to know not just the key passes and goals, but also the volume of passes intended to result in a shot.

Judging the intent of a pass is impossible from data, however we can safely assume that passes that are from outside of Zone 17 and going into Zone 17 have good intentions of generating a shot, if not a goal.

Let’s take a look at which passes are used to enter Zone 17:

As we can see from this visualization, crosses are the most frequent type of pass into Zone 17. This does not represent every cross attempt. Some are blocked or cleared. Some may even pass through Zone 17 untouched or miss Zone 17 altogether. The same could be true for through balls going out for goal kicks.

As seen with Goal Categories and key pass types, the allocations of these attempts are very consistent league-over-league and season-over-season. Smaller trends may emerge: for example, the rate of crossing into Zone 17 in the Bundesliga was lower than other leagues by 5% in 2014-15, but that number has been on the rise almost every season since then and now it matches the allocations seen in the other leagues.

Goals per 100 pass attempts into Zone 17 - 010721.png

What this chart tells us is that only one goal will be scored from crosses about every 40 attempts into Zone 17, even fewer as a percentage of total crosses when you consider all those that don’t make it into Zone 17. As other studies have shown, cross effectiveness can be increased by moving closer to the goal.

So while there are ways to improve crossing efficiency, it’s typically not the best option and often results in a clearance and usually results in losing possession. One of the biggest issues with crosses is the completion percentage, and thereby the chance just to create a shot, much less a goal from the shot, is low.

For efficiency, more through balls (13.2 per 100), cutbacks (6.4 per 100), and progressive balls (4.5 per 100) are likely to produce better results. Normal passes (4.1 per 100) from the sides of the box can also be effective, and we’ll look into why that is in a future article on the Basic Pass types.

Key pass effectiveness depends heavily on the source of the pass

As this visualization demonstrates, teams can be more efficient on the volume side playing progressive passes into Zone 14 and diagonally from Zones 13, 15, 16, and 18 into Zone 17. This will boost both the final third pass completion percentage and the chance of a goal. Through balls, which get in behind the defense, from Zone 14 and Zone 17 are one of the most effective ways of scoring goals regardless of their source. Any type of completed progressive pass within Zone 17 has a good-to-very good chance of being scored.

Combinations of Progressive passes, Through balls, and Cutbacks within and around Zone 17 are very lethal. Likewise, defending them is a huge problem. Reading and preventing those situations, which lead to defenders and keepers being out of position, or, worse, creating a penalty kick (with an ~80% scoring rate), will help any team reduce the number of conceded goals.

We can also use pass clustering to tell us the most useful passes to get into Zone 17 that result in goals.

How to use this information to your advantage

If we are analyzing an opponent, we want to understand not just where their shots come from, but also their attempts. Where other teams have had success preventing attacks or suppressing the most valuable opportunities, we want to consider their approaches.

This information also helps self-analysis. Are we creating valuable opportunities or just dumping in balls? Where is success being found? What types of passes? What angles? How can we be more efficient?

This information can also be valuable in scouting prospective players. For ideas on how to use this type of data to evaluate players, see Carl Carpenter's article on successful MLS teams and our visualizations in that article.

Key Points

There is consistency in each league and each season in the types of key passes and secondary key passes that create goals. Some goals may be scored by individual luck or skill, but most can be created by the right focus on team behavior. Understanding where to focus and what to deprioritize creates repetitive success over time.
Most crossing requires more volume than other types of passes in the Progressive Pass category which are more efficient. Teams usually end up losing possession after crossing, particularly in the air.
Retaining possession for a higher probability pass and shot allows teams to create a better scoring opportunity with both off-the-ball movements and patience. Move closer to the box or inside of it for higher-probability crosses.
Zone 17 analysis can help us identify what is working and not working and why. We can also analyze the passing patterns to and from other zones in our attacking phase, or even create a different set of zones, if needed, to analyze the use of half-spaces or other pre-key pass attacking play.

About Jamon Moore

Jamon is a twenty-five-year professional in the high-technology industry who started as a software developer and is now in executive management overseeing business agility transformations with a specialization in high-technology. In addition to his analysis for American Soccer Analysis, he is a credentialed media member covering the San Jose Earthquakes. Jamon can be contacted via Twitter, and club analysts and executives can connect with Jamon on LinkedIn.

About Carlon Carpenter

Carlon is the current Tactical & Video Analyst for StatsBomb, one of the largest soccer data companies in Europe. Carlon also works as a contract employee for the U.S. Soccer youth national teams, working as a performance analyst for the U-17 men’s national team. Carlon can be contacted through his LinkedIn account, or via Twitter.