New research shows that by participating in the UEFA Champions League, teams from the top five European football leagues – the English Premier League, the Bundesliga in Germany, La Liga in Spain, Ligue 1 in France and Serie A in Italy – improve their performance in their domestic leagues considerably. 

The study by Ilhan Guner and Mehdi Hamidi Sahneh finds that participation in the Champions League increases the probability of winning a game in domestic leagues by about 10 percentage points. Champions League participation also makes a team score on average 0.3 more goals per game.

The researchers delve into the mechanism through which Champions League participation causes performance gains. They show that playing against the stars of Europe makes a team better through mechanisms other than the transfers enabled by the prize money from the Champions League.

What might be such mechanisms? Potential mechanisms include:

  1. Anticipation of playing against the best teams of Europe encourages teams to take their training sessions more seriously and therefore physical fitness and tactical discipline gained on the training sessions and international games enable them to perform better.
  2. Teams learn from their international counterparts by playing against them and apply their learnings to domestic league games.


The authors call all these potential mechanisms as spillover effects. They construct two measures of performance: 

  1. An ex-ante measure of probability margin: how much probability the betting market gives a team to win a particular game above the probability given to the opponent’s win.
  2. An ex-post measure of goal difference: number of goals scored in a game minus the number of goals conceded.


In this study, they show that participation in the Champions League improves both ex-ante and ex-post performance. 

The first measure of performance is quite novel, and it relies on the remarkable predictive power of the betting market. 

One particular concern in attributing causal effect to Champions League participation is that teams that participate in the Champions League are intrinsically better teams: only the best teams of domestic leagues participate in the Champions League and it is quite natural for such teams to perform better than the teams not in the Champions League. 

The authors address this concern by comparing the performance of the teams that narrowly earned a Champions League spot with the teams that narrowly lost a Champions League spot. The teams lying on either side of the Champions League participation cut-off are comparable in other dimensions, therefore the better performance of teams barely made it to the Champions League must be due to causal effect of Champions League participation. 


Dancing with the Stars: Does Playing in Elite Tournaments Affect Performance?

Ilhan Guner and Mehdi Hamidi Sahneh


twitter: @gunerilhanva