I recently read somewhere (I wish I could remember where so that I could link to it) that OPTA uses the amount of passes in a game to determine possession. This surprised me. Basing possession on passing has the potential to produce some skewed results. The most obvious argument against this is that a team that uses the short passing game is going to have a larger portion of possession regardless of the actual amount of time that they truly have possession.
Then again, what other method can be put in place for measuring possession? The only thing I can think of is some guy sitting in the press box with binoculars and one of those timers that are used in chess matches. Needless to say, this wouldn't work. The person in the press box would have to determine when possession changes. There is a lot of grey area to navigate when it comes to defining what constitutes possession and what constitutes a loss of possession. All of this would be subject to interpretation by the person manning the chess clock. Even with a sport like American football, where things appear to be very cut and dry, defining possession is a point of contention (i.e. "Tuck Rule").
While using the amount of passes might not be a perfect metric to measure possession, it is clean, simple and minimizes any grey area. I decided to take OPTA's passing statistics and utilize it to look at possession on a more granular level. Upon doing this, I felt that I obtained some insight into Chicago's improvement over the past year and how the team is beginning to gel now that they're in season form.
When I think back to last year's season, One of the most frustrating things about watching them was the fact that the team struggled to maintain possession. Passing was sloppy, and players did not seem to be on the same page much of the time. At times, it was like watching clowns fight over who called shotgun to the clown car. The one player who comes straight to mind when I recall last year is Diego Chaves. Diego would drop back in to the midfield and work hard at trying to link passes together to get the ball up the field. More often than not, it would all end in a disparaged and frustrated Diego Chaves.
Even though Chicago improved towards the end of last season, they started off the new 2012 season fairly flat. Thanks to some strange scheduling, Chicago had a prolonged stay in preseason mode. In the first 5 matches of the season, Chicago never once out possessed their opponent. Their lowest possession point came in the mile high drubbing against Colorado at 40%. Typically when a team goes down by a goal or more, their opponent sits back and defends. In the case of the Colorado match, the Fire were getting beat in the midfield. Eventually, desperation set in and the Fire resorted to blasting the ball down field to catch Oduro on a quick break. More often than not, Oduro would not be able to get toe the ball and Colorado would have possession again. The highest possession rate in the first 5 matches? 46.8% in the season opener again Montreal.
Match 6 against the Sounders was were things started to change for the Fire. Even though the result was a loss, there was muted optimism at how the team performed. The Fire showed some promising signs against the Sounders and managed to finish the game with the majority of the possession at 54%. The only thing that stood between Chicago and victory was a couple of fluky goals. Since that match, Chicago has done well with possession: 48% (@Chivas), 54.3% (RSL), and 58% (SKC). Granted, this is still a fairly small sample size, but it appears that the Fire are starting to get into a rhythm, allowing them to maintain possession.
The matches against Real Salt Lake and Sporting KC had two distinctly different feels to them. RSL did not come to Chicago at entirely full strength, but even then, their starting XI were nothing to laugh at, and the Fire looked strong through much of the match. Sporting, on the other hand, came to play, and after the first 45 minutes, things were not looking good for the Fire.
What I did with OPTA is simple. I broke the field into thirds (Defense, Midfield, and Attacking) and recorded passing statistics from each third. I also used the timeline bar to divide the passes between halves. After that, it was all spreadsheets and formulas.
To get a full view of the the charts below, just click on them. Also, I forgot to label the passes as complete and incomplete. For each section the left number represents complete passes and the right number represents incomplete passes. Lastly, the possession % section represents how much of each team's possession occurred in that part of the field
The RSL Match
The first two numbers that jump out at me for the Real Salt Lake match is how the Fire had nearly 13% of their first half possession in the attacking end of the field. The downside is that the Fire's completion percentage drops off fairly significantly in the final third. There was a bit of role swapping between RSL and the Fire as RSL seemed to have the attacking edge in the second half.
Another observation that sticks out is the defensive end in the second half. The Fire's possession increases there, but their completion percentage drops. This could be part of the reason behind RSL's 13.5% possession in the attacking third during the second half.
The fact that the Fire were able to keep nearly 80% completion rate and maintain two-thirds of their possession in the midfield pretty impressive. It's pretty safe to say the that Fire won the midfield battle in this match.
Sporting KC Match
The big number here is that the Fire were able to keep a fairly high completion rate in the midfield against a team like Sporting. However, the totals tell a different story than each individual half. There is a spike in the midfield possession and completion numbers between the first half and the second half. This spike is directly correlated to Roger Espinoza's red card. After Espinoza saw red, the Fire completed 90% of their passes in the midfield. However, for the 17 minutes before Espinoza was sent off, the Fire had already attempted over 100 passes and were already completing passes at 83%. The Fire were starting to take the midfield away.
Peter Vermes and the Spork fans can say, "durr...the ref changed the game...durr..." until they're blue in the face. The fact is that a different Fire team came out in the second half. Maybe without the red, this game ends in a draw, but there was no way that Sporting was leaving Chicago with three points.
It's nice to see that Chicago is starting to do better at keeping possession and passing the ball better in the midfield. Still, possession and good passing does not automatically turn into wins. It helps, but it's not a necessity. The amount of possession the Fire had in these two games and their completion percentage in the final third is something to be concerned of. Granted these numbers are going to be naturally low, but my guess is that these numbers are lower that of the top teams in the league.
Part of these low numbers has to do with Oduro. He's great for breakaways, but since the Fire haven't had too many of those this year, he's turned into a poacher. Naturally, this leads to the discussion that has been beaten beyond recognition regarding our need for a striker with a style different than Oduro's. Yes, we have Chris Rolfe, but I'm still skeptical about Rolfe at this point. Either way, the Fire do need to figure something out to fix the issue they're having in the attacking third of the field.