Research on the effect of athlete leadership on precursors of team performance such as team confidence is sparse. To explore the underlying mechanisms of how athlete leaders impact their team’s confidence, an online survey was completed by 2,867 players and coaches from nine different team sports in Flanders (Belgium). We distinguished between two types of team confidence: collective efficacy, assessed by the CEQS subscales of effort, persistence, preparation, and unity; and team outcome confidence, measured by the ability subscale. The results demonstrated that the perceived quality of athlete leaders was positively related to participants’ team outcome confidence. The present findings are the first in sport settings to highlight the potential value of collective efficacy and team identification as underlying processes. Because high-quality leaders strengthen team members’ identification with the team, the current study also provides initial evidence for the applicability of the identity based leadership approach in sport settings.