This study examined the relationship between the outcomes and playing opportunities of the match immediately after the survey (next match), and the collective effectiveness and group cohesiveness of high school and university rugby players. The sample comprised 530 players from 9 high school teams, and 820 players from 9 university teams. They were classified into four groups according to the next match outcomes (before winning/before losing) and match playing opportunities (roster/non-roster). The Japanese translations of the Collective Efficacy Questionnaire for Sports and the Group Environment Questionnaire were used to measure collective efficacy and group cohesiveness, respectively. A two-factor analysis of variance was performed with winning or losing, and playing opportunity of the next game as the independent variable, and the score on the scales as the dependent variable. Results showed that the collective efficacy was higher in the group of high school players on the roster, before winning the next game. In contrast, group cohesiveness was not related to the next match outcomes for both high school and university players. In addition, both high school and university players had higher values in the roster group for both collective efficacy and group cohesiveness, regardless of the next match outcomes. Therefore, collective efficacy was related to winning or losing the next game only for the group of high school players on the roster.
