Why Chelsea Lost the 2008 UEFA Champions League final
https://econfix.wordpress.com/2011/03/14/game-theory-penalties-and-the-champions-league-final-2008/
Anybody who watches soccer will know that a penalty shootout is probably one of the most nerve-racking situations in the entire sport. The anxiety it induces is partly because its outcome determines which team will advance in a competition and which team will be disqualified. The other stressful aspect is that it nullifies the previous 120 minutes of arduous, tactically-trying gameplay in favour a few kicks from 12 yards. A few seemingly random kicks that may not fairly reward the better team.
However, penalty shootouts are not as random as one might think. They themselves are a game that relies heavily on tactics and strategies, just as the entire sport does. As is detailed in the article, a penalty kick can be modelled as a game played by two players: player 1 is the Kicker and player 2 is the Goalkeeper. Players can kick the ball to the middle of the goal, to the “natural side” (which will be the goalkeeper’s left side if the player is left-footed, and the goalkeeper’s right-side if the player is right footed), or the “opposite side”.
Before the 2008 UEFA Champions League final, a game was developed including Manchester United goalkeeper, Edwin Van der Sar, as player 2, and all the kickers he had faced in penalty kicks as player 1. The game created was then used to advise the kickers on the side they should choose in order to maximise their chances of scoring against the goalkeeper in the event that the match went all the way to a penalty shootout, which is exactly what happened.
The application of the developed game proved largely successful: when the advice given based on the game and the analysis of the goalkeeper was followed, not a single penalty kick was saved by the goalkeeper (although one of the six was missed by a kicker). The success was largely because the goalkeeper was not aware of the game and the payoffs. However, when the goalkeeper became aware of the game being played, he made this known to the kicker. The kicker was thrown into a conundrum and did not employ the best strategy in the situation. His failure to do so resulted in the penalty being saved – the only penalty that the goalkeeper saved that night. As a result, the kicker’s team lost the final.
Developing a game is interesting, but applying it to a real-life circumstance shows just how powerful game theory is. Additionally, this shows that a penalty shootout is not just a bunch of random kicks that unfairly determine the outcome of a match. They too require tactics and strategies, and thus, one might argue, they fairly reward the better team.