The rise of data analysis in football

This exposed the problems with applying statistics to outfield action. Football was always going to have trouble utilising analytics, but it does appear to have recovered from the Comolli-induced wobble. Clubs are still largely run by individuals who believe they can rely on gut instinct rather than any form of data analysis, but the strength of good data is starting to erode this primitive view as it did in baseball. Data is hugely prominent in the sport today and even more so than it was before Moneyball was written – whether this is a coincidence or not. The only answer to Comolliesque bad data, is more data; good data and better data, not no data at all.

And better data has followed. Stoke City, under Pulis, analysed throw-ins, Manchester City under Mancini analysed corners, and people like Palacios-Huerta are analysing free-kicks as well. We have more data for the optimum time substitutes should be introduced, emerging data on player conditioning, and Comolli can be thankful that many in-game scenarios are being studied too. And better data tells us extraordinary things. Corners for example, like crosses, are terrifically bad at producing goals.

As Sally and Anderson reveal, in their book ‘the Numbers Game: Why Everything You Know About Football is Wrong‘, ‘when we combine the odds of corners generating a shot on goal plus the odds that these shots will find the back of the net, our data show that the average corner is worth about 0.022 goals, or – more simply – that the average Premier League team scores a goal from a corner once every ten games’.

This view doesn’t really seem consistent with the masses of fans who celebrate a corner like they’ve scored a last minute winner. ‘89 per cent of shots on goal produced from corners are wasted‘, Sally and Anderson add. And this data can be put to use. Real Salt Lake, an American MLS team (where data in sports in taken more seriously), are one team seemingly making use of short corners to exploit this, from the logical viewpoint that surrendering the ball for 0.022 of a goal is a bad idea.

Short corners also give a numerical advantage in the penalty area as well, as Devin Pleuler, a data analyst with the MLS puts forward, ‘RSL, as well as a handful of other MLS clubs (and even the US national team on occasion), have commonly been setting up for corner kicks with two attacking players near the corner – regardless if they eventually attempt a short corner or not. Usually, the defending team is forced to send two defenders in response. When this happens, a very subtle numerical shift occurs in favour of the attacking team’. The resulting set-pieces may look strange, but the application of this information gives Real Salt Lake a competitive advantage.

Roberto Mancini, the former Manchester City manager, owes some of his only Premiership trophy to the use of data from corners too. Simon Kuper, one of the founders of the Soccernomics Consultancy Agency for football teams and co-author of ‘Why England Lose: And other curious phenomena explained‘ details, ‘analysts finally persuaded the club’s then manager, Roberto Mancini, that the most dangerous corner kick is the inswinger, the ball that swings towards goal. Mancini had long argued (strictly from intuition) that outswingers were best. Eventually he capitulated and, in the 2011-2012 season, when City won the English title, they scored 15 goals from corners, the most in the Premier League. The decisive goal, Vincent Kompany’s header against Manchester United, came from an in swinging corner.”.

This shows how good data when practically applied can give you an edge. Not a lot of championships were as close as the 2011-2012 Premier League season to which Kuper refers, so those 15 goals were huge. Football teams are using this kind of information more and more.

Substitutes have also been covered in some detail by ex-player (and frequently benched) Bret Myers. Dr Myers, who is now working as an assistant professor at the Villanova School of Business in Pennsylvania, found the optimum time to introduce substitutes when a team were losing the match. Jared Diamond of the Wall Street Journal, who wrote a short piece on Myers, cited that he ‘concluded that if their team is behind, managers should make the first substitution prior to the 58th minute, the second substitution prior to the 73rd minute and the third prior to the 79th minute. Teams that follow these guidelines improve—score at least one goal—roughly 36% of the time. Teams that don’t follow the rule improve about 18.5% of the time. He noted 1,037 instances the rule could have been applied and found that managers abide by it a little less than half the time‘.