# Predicting Qualification Thresholds in UEFA's incomplete round-robin tournaments

## TL;DR

This paper models and predicts qualification thresholds in UEFA's new incomplete round-robin tournament format using a bivariate Dixon--Coles model and Elo ratings, providing strategic insights.

## Contribution

It introduces a statistical approach to estimate qualification thresholds accounting for reduced draws, improving decision-making in UEFA's new tournament structure.

## Key findings

- The model accurately estimates qualification thresholds for UEFA's new format.
- Reduced incentives lead to fewer draws, affecting match outcome distributions.
- Simulation results support strategic planning for clubs and managers.

## Abstract

For the 2024/25 season, the Union of European Football Associations (UEFA) introduced an incomplete round-robin format in the Champions League and Europa League, replacing the traditional group stage with a single league table of all 36 teams. Under this structure, the top eight teams advance directly to the round of 16, while teams ranked 9th-24th qualify for a play-off round. Simulation-based analyses, such as those by commercial data analyst Opta, provide indicative point thresholds for qualification but reveal deviations when compared with actual outcomes in the first season. To overcome these discrepancies, we employ a bivariate Dixon--Coles model that accounts for the lower frequency of draws observed in the 2024/25 Champions League season, potentially driven by reduced incentives for teams to play for a draw. We proxy team strengths by Elo ratings and fit the model to different settings. This enables us to simulate match outcomes and to estimate qualification thresholds for both direct advancement and play-off participation. Our results provide scientific guidance for clubs and managers, supporting strategic decision-making under uncertainty regarding their progression prospects in the new UEFA club competition formats.