The new construct of integrated temporal positivity—defined as the positive, adaptive, and dynamic use of the past, the present, and the future—is posited to promote optimal functioning. Based on the dualistic model of passion, the present research sought to test the hypothesis that harmonious passion, more than obsessive passion, triggers a higher use of integrated temporal positivity that, in turn, leads to one crucial type of sport performance, namely last-second performance. The results of 3 studies conducted with team-sport athletes (Study 1, n = 625; Study 2, n = 285; and Study 3, n = 263) provided clear support for the hypothesis. The results pave the way for future research focusing on the role of adaptive temporal processes in support of sport performance.