Bringing on substitutes in a football match to avoid shock defeat can actually makes matters worse, according to new research published at the University of Warwick.
The research, co-founded by Warwick Business School’s Dr Leif Brandes, examined the tactical habits of professional managers in 3,672 matches in the German Bundesliga, from 1998 – 99 to 2009 – 10, and 4,560 games in the English Premier League, between 2000 – 01 to 2011 – 12.
As well as bringing on a substitution that made minimal impact, the research additionally found that teams heading for a shock defeat were 85 percent more likely to receive a card for violent conduct.
Alongside Björn Bartling, of the University of Zurich, and Daniel Schunk, of the University of Mainz, Dr Brandes found that many professional managers make numerous mistakes when trailing to a side they are expected to beat, despite their reputation as ‘tactical geniuses’.
Dr Brandes said: “Our research shows that coaches implement offensive strategy changes by means of substitutions, for example a striker for a defender, significantly more often if their teams are behind expectations than if their teams are not behind expectations.
“Despite the push to bring on another striker to help bring the score back in favour of the team expected to win, our research found such an action actually had negative consequences, with on average it worsening their goal difference by 0.3, while they were also 0.3 points worse off.”
He added: “When the bookies favourites are behind we found they also receive more cards, 14 percent more cards per minute. This, plus substituting players in an offensive way while being behind expectations sees them concede more goals and give up more points.”
The study also found fewer goals are scored in the Premier League compared to the Bundesliga,
with 2.63 goals per match in England compared to 2.85 in Germany while fewer cards are handed out (3.26 cards per match compared to 4.31).
Oli Steel, a second-year Physics student, remarked upon the findings. He commented: “The research is really quirky and I am glad the University is not just sticking to conventional academia.
“As for the content of the findings, it does not come as much a surprise that top managers panic and make misjudged substitutions when losing, it happens all the time!”