Passing: An oddity in how it's measured in Soccer (Part II) / by Drew Olsen

If you read my initial article on "Passing - An oddity in how it's measured in Soccer Part I"; I hope you find this article of value as well as the onion gets peeled back a bit further  to focus on Crosses. To begin please consider the different definitions of passing identified in Part I and then take some time to review these two additional articles (Football Basics - Crossing) & (Football Basics - The Passing Checklist) published by Leo Chan - Football Performance Analysis, adding context to two books written by Charles Hughes in 1987 (Soccer Tactics and Skills) and 1990 (The Winning Formula).   My thanks to Sean McAuley, Assistant Head Coach for the Portland Timbers, for providing these insightful references.

In asking John Galas, Head Coach of newly formed Lane United FC in Eugene, Oregon here's what he had to offer:

"If a cross isn’t a pass, should we omit any long ball passing stats? To suggest a cross is not a pass [is] ridiculous, it is without a doubt a pass, successful or not - just ask Manchester United, they ‘passed’ the ball a record 81 times from the flank against Fulham a few weeks back.”

In asking Jamie Clark, Head Coach for Soccer at the University of Washington these were his thoughts...

"It's criminal that crosses aren't considered passing statistically speaking. Any coach or player knows the art and skill of passing and realizes the importance of crossing as it's often the final pass leading to a goal. If anything, successful passes should count and unsuccessful shouldn't as it's more like a shot in many ways that has, I'm guessing, little chance of being successful statistically speaking yet necessary and incredibly important."

Once you've taken the time to read through those articles, and mulled over the additional thoughts from John Galas and Jamie Clark, consider this table.

 Stat Golazo/MLS STATS Squawka Whoscored MLS Chalkboard My approach Different (Yes/No)?
Total Passes 369 356 412  309+125 = 434 309+125+9=443 Yes
Total Successful Passes 277 270 305 309 309 + 9 = 318 Yes
Passing Accuracy 75% 76% 74% NOT OFFERED 71.78% Yes
Possession Percentage 55.30% 53% 55% NOT OFFERED 55.93% Yes
Final Third Passes 141 NOT OFFERED NOT OFFERED FILTER TO CREATE 140 Yes
Final Third Passing Accuracy 89/141= 63.12% NOT OFFERED NOT OFFERED FILTER TO CREATE 92/140 = 65.71% Yes
Total Crosses 35  vs 26 (MLS Stats) NOT OFFERED 35 35 35 No
Successful Crosses 35*.257=9 NOT OFFERED 9 9 9 No
KEY PASSES NOT OFFERED 7 9 6 6 Yes
 

* NOTE: MLS Chalkboard includes unsuccessful crosses as part of their unsuccessful passes total but does not include successful crosses as part of their total successful passes; it must be done manually.

For many, these differences might not mean very much but if looking for correlations and considering R-squared values that go to four significant digits these variations in datum might present an issue.

I don't track individual players but Harrison and  Matthias do, as does Colin Trainor, who offered up a great comment in the Part I series that may help others figure out where good individual data sources might come from.

What's next?

My intent here is not to simply offer up a problem without a solution; I have a few thoughts on a way forward but before getting there I wanted to offer up what OPTA responded with first:

I (OPTA representative) have has (had) a word with our editorial team who handle the different variables that we collect. There is no overlay from crosses to passes as you mentions, they are completely different data variables. This is a decision made as it fits in with the football industry more. Crosses are discussed and analysed as separate to passes in this sense. We have 16 different types of passes on our F24 feed in addition to the cross variable.

So OPTA doesn't consider a cross a pass - they consider it a 'variable'?!?

Well I agree that it is a variable as well and can (and should) be tracked separately for other reasons; but for me it's subservient to a pass first and therefore should be counted in the overall passing category that directly influences a teams' percentage of possession.  Put another way; it's a cross - but first and foremost it's a pass.

(Perhaps?) OPTA (PERFORM GROUP now) and others in the soccer statistics industry may reconsider how they track passes?

I am also hopeful that OPTA might create a 'hot button' on the MLS Chalkboard that allows analysts the ability to filter the final third consistently, from game to game to game, as an improvement over the already useful 'filter cross-hairs'...

In closing...

My intent is not to call out any statistical organizations but to offer up for others, who have a passion for soccer analyses, that there are differences in how some statistics can be presented, interpreted and offered up for consideration.  In my own Possession with Purpose analysis every ball movement from one player to another is considered in calculating team passing data.

Perhaps this comparison is misplaced, but would we expect the NFL to call a 'screen pass' a non-pass and a variation of a pass that isn't counted in the overall totals for a Team and Quarterback's completion rating?

Here's a great exampleon how Possession Percentage is being interpreted that might indicate a trend.

Ben has done some great research and sourced MLS Stats (as appropriate) in providing his data - he's also offered up that calculating possession is an issue in the analytical field of soccer as well.

In peeling back the data provided by MLS Stats he is absolutely correct that the trend is what it is... When adding crosses and other passing activities excluded by MLS Stats the picture is quite different and lends credence to what Bradley offers.

For example--when adding crosses and other passing activities not included by MLS Stats--the possession percentages for teams change, and the R-squared between points in the league table comes out as 0.353, with only 7 of 8 possession-based teams making the playoffs. New York, with most points, New England and Colorado all had possession percentages last year that fell below 50%, and only one team in MLS last year that didn't make the playoffs finished with the worst record (16 points) DC United.

For me, that was superb research - a great conclusion that was statistically supported. Yet, when viewed with a different lens on what events are counted as passes, the results are completely different.

All the best,

Chris

You can follow me on twitter @chrisgluckpwp