UEFA Champions League entry has not satisfied strategyproofness in three seasons

TL;DR

This paper examines the UEFA Champions League qualification process over three seasons, revealing strategic vulnerabilities where teams could benefit from losing matches, and proposes a rule change to improve fairness.

Contribution

It identifies specific instances where the current qualification system fails strategy-proofness and suggests a straightforward incentive-compatible rule to address this issue.

Findings

In three seasons, teams could have benefited from losing matches.

The current qualification system is not strategy-proof.

A proposed rule could prevent strategic manipulation.

Abstract

The paper investigates the qualification for the UEFA Champions League, the most prestigious club competition in European football with respect to the theoretical property of strategy-proofness. We find that in three seasons (2015-16, 2016-17, 2017-18), the UEFA Europa League titleholder might have been better off by losing its match against the Champions League titleholder in their domestic championship. A straightforward solution is suggested in order to avoid the occurrence of this paradox. The use of an incentive compatible rule would have a real effect on the qualification in these three seasons of the UEFA Champions League.