The eyes don’t have it: Coaches’ eye is not a valid method of estimating biological maturation in male Gaelic football

In youth sport, coaches often rely on subjective assessments of current ability and future potential, which may favor players advanced in biological maturation. This study evaluated the accuracy of coaches’ maturity assessments and their impact on perceptions of player ability and potential, as well the inter-coach agreement on talent and maturity evaluations. Maturity timing (discrepancy between biological and chronological age) was assessed using the Khamis-Roche method for 247 male players aged 13 to 17 years. Eighteen coaches provided estimations of their players’ maturity timing, ratings of current ability and long-term potential, and selections of top and bottom 5 players. Inter-rater reliability was calculated using weighted Kappa (k) and percentage agreement. Kendall correlation analyses (τ) examined relationships between maturity and coaches’ perceptions, while a Kruskal Wallis test examined differences in maturity between players classified by coaches as top, middle and bottom performers. On average, coaches underestimated the presence of early maturers and overestimated on-time and late maturers. Maturation timing showed weak correlations with current ability (τ = 0.075) and future potential (τ = 0.021). Coaches’ selected “top” players did not differ in maturity from their peers (H2 = 4.844, p = 0.89). Agreement between coaches ranged from none to weak. These findings suggest coaches’ eye may be inaccurate for estimating maturation. Additionally, there is poor inter-coach agreement in identifying talented athletes, indicating the “coach's eye” is subjective and variable. These results may have significant implications for future talent identification research and processes in sport organizations.