The main goal of the study is to examine the evolution of players' perception of cohesion and efficacy over the season and their relation with success expectations. The research sample comprised 146 male soccer players, aged between 15 and 19 years (M = 16.96, SD = .76). Diverse instruments were used to measure cohesion, perceived efficacy, and success expectations. The most noteworthy results show that players whose expectations do not match the team's final performance will experience a negative evolution of their levels of perceived cohesion and efficacy, whereas players whose expectations at the start of the season match the team's final performance in the classification will maintain their degree of perceived cohesion and efficacy. The main conclusion of the study is that coaches and sport psychologists should attempt to clarify the players' basic goals of the season to create expectations that match what is expected from the team.
Keywords: cohesion; efficacy; performance; soccer; success expectations.