City Substitutions - Science Or Intuition?
There are many benchmarks for judging the ability of a football manager. Results are certainly a key indicator - just ask Roberto Di Matteo or Mark Hughes. Their ability to motivate a squad of players is another, especially when working on a tight budget or without the boost of a transfer window to provide the impetus of fresh blood to an underperforming team. The quality of the signings that managers make is often held as a sign that a manager has the cachet to attract the best in the game. After all, these are HIS players, they will shape the look of HIS team and deliver HIS style of play.
Many opportunities exist within the day-to-day life of a football club for managers to demonstrate their ability to influence team performance. Perhaps in the training sessions the week before the match they will have drilled the players on their positional roles at set pieces, or practised a counter attacking strategy or given specific instructions on how to manage a particular opponent. Through their man management skills they may have earned trust of the players and ensured their commitment which can lead them to go that extra yard, to put in that last ditch tackle for the team, to track back to help out their team mate in the dying minutes of a game. And on match day they may have given a stirring talk in the dressing room to fire up the team to deliver the performance the fans (and owners) want to see.
But when it comes to actually managing on the day of a game under scrutiny of the media and the fans, once the team selection has been made and the chosen 11 have crossed the white line then how can the manager influence the game? We often see them gesticulating on the touchline or rushing to the edge of the technical area to bellow at the players despite the fact that their words can barely be heard by the players in the dugout let alone the errant winger on the opposite side of the pitch such is the noise in a modern football stadium. What else can they do?
They can change some of the players.
Are substitutions the product of experience and judgement or are they just a 'last throw of the dice'? Moreover, does it make any difference at all when the changes are made?
I doubt whether any City fan would deny that the substitutions made by Mancini at the Etihad on the afternoon of 13th May 2012 had no impact. Edin Dzeko (69 minutes), played a major role on that day scoring the critical equaliser and then, in the dying seconds off added time, Mancini's third substitution, Mario Balotelli (75 minutes), having fallen to the ground on the edge of the QPR penalty area deliberately poked the ball into the path of Aguero and the rest, as they say, is history.
Remember the timings of those second and third changes. We'll come back to that.
Edin Dzeko's continued impact as a substitute during the current season has been the subject of much comment and would continue to be a testament surely to the effectiveness of a 'well timed' change of playing personnel. But is there a science to it? Is there a model, a defined strategy, which can help managers make these decisions?
Bret Myers, a professor of management and operations at the Villanova School of Business, believes that there is. In 2011, he published a paper - 'A Proposed Decision Rule for the Timing of Soccer substitutions' based on over 1200 observations collected from some of the World's top professional leagues and competitions. He concluded that:-
'Heading into the second half of a game, if your side is behind, it is important to make your first substitution prior to the 58th minute. If you are still behind, the second change needs to come before the 73rd minute. If still behind, the third and final change should be made before the 79th minute.'
His study assumes that the strategy is successful if the 'goal difference is improved in the end.' Professor Myers also concluded 'It has been found that teams are roughly 40 to 45 per cent successful when following the rule and 18 to 22 per cent when not.'
In other words: if a team is losing, and the manager does not follow this substitution pattern, the team has a one in five chance of turning the result around. By following the pattern he almost doubles his odds for success.
Prior to 23rd November, the proportion of Premier League wins where the successful team had trailed was 23.8%. Last season this applied to only 15% of victories. Is this a coincidence or an indication of the increasing impact of this area of sports science influencing decision making? The substitution timings for these matches would be interesting to read.
The use of performance data in football has been growing since the pioneering use of Pro Zone by Sam Allardyce at Bolton. Premier League clubs employ teams of analysts to provide data to coaches and players themselves and, as recently as November 2012 at the second Sports Analytics Conference held in Manchester, representatives from nearly every Premier League club as well as from the nPower Championship, rugby league and the England and Wales Cricket Board pitched up to hear Myers, amongst others, speak. Whilst football is not baseball and there is unlikely to be any 'Moneyball' revelation, nevertheless the clubs are stepping increasingly into this area because they believe that they can improve their chances of success if they have more knowledge.
Manchester City F.C. clearly do as the club's commitment to Performance Analysis and their ground breaking collaborative 'MCFC Analytics' programme attests: MCFC Analytics
58-73-79. That is the 'Decision Rule' substitution pattern advocated by Professor Myers. Can we see this 'rule' at work in the timing of City substitutions?
The delivery of the first league title in 44 years to Manchester City owed a significant amount to the contribution of the substitutes. City fell 1-2 behind to that sickening Mackie header in the 66th minute. Remember the timings mentioned earlier? Dzeko came on at 69 minutes and Balotelli at 75 minutes. The provider of the pass to Aguero to set up the one-two with Balotelli for the winning goal. Nigel de Jong. He was brought on as a substitute in the 44th minute. Intuition and managerial experience or science?
In nine of the twenty matches City have played in all competitions since the start of the 2012/13 season they have been behind and then gone on to improve the result, winning four of the games and drawing the remainder. In five of those nine matches the second substitution was made before the 73rd minute whilst City were either behind or drawing and in each of these games the outcome was improved. City turning losing positions into wins against Southampton & Spurs and draws against Liverpool, Ajax and Real Madrid. In two other games (against Fulham and WBA) the second substitutions were made in the 76th and 79th minute respectively. City were losing when these substitutions were made. They went on to win both matches.
It is clear that there cannot be a single magic formula for winning matches (the application of Fergie Time notwithstanding) and there are a myriad of other factors which can affect the outcome of matches. These include the need to make substitutions for injuries - for example Aguero was taken off injured in the 14th minute against Southampton - as well as the personnel used, a change in formation or the vagaries of decisions by officials. City were not awarded a last minute penalty against Ajax at home but did get a penalty against Real Madrid. Those decisions could just as easily have been reversed.
The games used in this very 'quick and dirty' analysis clearly do not prove the theory is correct and the application of this kind of science to football does not always sit well with everyone. But it makes me look more closely at the nature and timing of substitutions made during games adds another dimension to the interest in a match. It certainly made me think that the introduction of Balotelli in the 86th minute against Chelsea was too late.
Whether it can help to improve my own performance at the VMC Forum 'Can You Manage the Team' challenge is another question entirely...!
VMC FORUM: City vs. Everton - Can You Manage the Team?
all times East Manchester
Sa 01Dec 15h00 Everton, The Etihad, PL
Tu 04Dec 19h45 B Dortmund, Signal Iduna Park, CL
Su 09Dec 13h30 The rags, The Etihad, PL
Sa 15Dec 12h45 Newcastle, St James' Park, PL
Sa 22Dec 15h00 Reading, The Etihad, PL
We 26Dec 15h00 Sunderland, Stadium of Light, PL
Sa 29Dec 15h00 Norwich, Carrow Road, PL