Overuse injuries, which have a high prevalence in sport, are suggested to result in different affective responses in comparison to traumatic injuries. Affects may also reciprocally act as risk factors for overuse injury. The aim of this study was to examine the associations between overuse injury and affects within a longitudinal follow-up design. Competitive athletes (N = 149) of various sports and levels of competition completed the Positive and Negative Affect Schedule (PANAS) and the Oslo Sports Trauma Research Centre Overuse injury questionnaire (OSTRC-O) once a week over 10 consecutive weeks. Bivariate unconditional latent curve model analyses with structured residuals were performed to evaluate the associations within and across weeks between OSTRC-O severity score and affects. Results indicated that OSTRC-O severity score and positive affects (PA) had a statistically significant negative within-week relation (r = −24.51, 95% CI = [−33.9, −15.1], p < 0.001). Higher scores of overuse injury were significantly related to lower levels of PA across weeks (ß = −0.02, 95% CI = [−0.04, −0.001], p = 0.044), while the reciprocal effect of PA on overuse injury was not significant (ß = −0.13, 95% CI = [−0.52, 0.26], p = 0.51). No statistically significant association was observed between OSTRC-O severity score and negative affects, neither within nor across weeks. Our findings suggest that overuse injury may have adverse psychological consequences on the long run through lessened PA and address the need for providing sustainable psychological support focusing upon such PA when working with athletes experiencing overuse injury. © 2024 The Author(s). Scandinavian Journal of Medicine & Science In Sports published by John Wiley & Sons Ltd.