© 2014 Sports Medicine Australia. Objectives: This study examined the association between self-reported mental toughness and behavioural perseverance among a sample of male Australian footballers in a naturalistic context. DesignCross-sectional field study, with the multistage 20 m shuttle run test (MST) employed as a proxy for behavioural perseverance. Methods: 330 male Australian footballers aged between 15 and 18 years (M=16.86; SD=.71) with between 2 and 14 years playing experience (M=9.32; SD=2.51) participated. Initially, footballers completed a mental toughness questionnaire, before having their height and body mass measurements taken. Subsequently, a performance testing session was completed, which included the 20 m sprint, Australian football-specific agility run, vertical jump, and the MST. Bayesian estimation was employed to allow for the simultaneous examination of existing findings with our new data in a way that provides an automatic meta-analysis of evidence in this area. Results: The analysis indicated a 95% probability that the association between mental toughness and behavioural perseverance lies between .14 and .34, even when controlling for other factors known to influence MST performance, including age, height, body mass, and years playing experience. Conclusions: Taken together with previous research, these findings support the theoretical proposition that persistence, effort or perseverance represents a behavioural signature of mental toughness.