Performance crises in professional soccer: developing and validating crisis indices for team performance assessment = Leistungskrisen im Profifußball: Entwicklung und Validierung von Krisenindizes zur Bewertung der Mannschaftsleistung

Performance crises in professional soccer impact team cohesion, confidence, decision-making, and stakeholder satisfaction. This study develops and validates three quantitative indices—Relative Position (RP), Linear Rate of Change (LRC), and Exponential Rate of Change (ERC)—to assess team performance relative to expectations and detect crises. Using data from the 2023–2024 Bundesliga season, the indices were applied to analyze underperformance patterns and their connection to managerial changes, offering insights into the psychological dynamics of team crises. The RP index measures deviations from preseason expectations, LRC captures cumulative performance trends, and ERC reflects recent momentum, identifying acute downturns that may trigger crises. Results show that the indices effectively diagnose chronic and acute performance issues, with sharp ERC declines often preceding coaching dismissals, signaling key psychological tipping points in decision-making. Case studies of FC Augsburg and VfL Wolfsburg illustrate the indices’ practical application, highlighting contrasting patterns of early versus late managerial interventions. Teams experiencing coaching changes exhibited significant negative trends in all three indices, reinforcing their reliability in identifying crises. ... mehrBy integrating psychological momentum, expectation management, and performance analysis, the indices offer a systematic framework for monitoring team performance and informing timely interventions.