SSA Blog: Why change a keeper?
Kepa Arrizabalaga was sent on late in the Carabao Cup final as a penalty specialist. This tactic has been used previously for penalty takers but it is rare for keepers to be switched.
Kepa Arrizabalaga conceeded 11 penalties during the Carabao cup final
The concept of specialist players isn’t a new one when looking across international sport. American sports such as football and basketball are perhaps the most obvious examples. American football has specialist kickers and even special teams squads. In basketball depending on the game situation it is common to see coaches rotate players on an offence, defence basis. Closer to home, rugby has progressed to the notion of finishers rather than substitutes, a sign that players who are not starting will come off the bench to fulfil a specialist role.
Many fans and pundits have questioned the decision to bring on Kepa specifically for the penalty shootout, but he does have previous. In his last shootout, he was brought on and made two saves to help Chelsea win the UEFA super cup. But was it the right call to bring him on against Liverpool in the Carabao Cup final? A deeper look into the stats reveals that, although Kepa does have a good record, the decision to bring him in may have more to do with his goalkeeping colleague and current Chelsea number one, Edouard Mendy.
Mendy has been exceptional for Chelsea. He has also been fantastic for his country. Playing for Senegal in the Africa Cup of Nations he didn’t concede a goal until the quarter-finals. In a tournament the Lions of Teranga went on to win, he only conceded two goals from open play.
However, his record when facing penalties does offer cause for concern. Manchester City fans will remember Mendy saving Sergio Aguero’s terrible ‘Panenka’ but otherwise his saves are few and far between. As a pro, Mendy has faced a total of 58 penalties, 32 during games and 26 in shootouts. Of those, 48 have been scored, an 83% success rate for the taker. In contrast, Kepa has faced 64 penalties and conceded 44 of them. This is a 69% success rate for the opposition.
According to data from InStat 75.6% of penalties are scored across men’s football. Kepa’s success rate sees him on the right side of this average. Mendy’s numbers point in the other direction. When faced with a clear breakdown, it’s hard to argue that with a trophy on the line, and the ability to make a change, Thomas Tuchel made the wrong decision to bring in Kepa.
Of course, sport isn’t played on paper, players still need to execute their skills, in the face of opposition ability and high-pressure environments. On this occasion, the change didn’t work for Kepa,Tuchel or Chelsea.
The role of a goalkeeper is, by its nature a specialist one in football. A penalty shootout is also a very specialist situation. It’s impossible to know if Mendy would have fared better during the shoot out. The statistics suggest he wouldn’t. A number of pundits have labelled the change as ‘nonsense’ and ‘costing Chelsea the cup’. However, when faced with such stark statistics, regarding a specialist role for a specialist situation, perhaps the nonsense decision would have been not making the change
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