ABSTRACT Research question A growing body of research in sport literature links athlete racial advocacy to social justice. However, less is known about how athletes drive individual-level cognitive outcomes and contribute to the achievement of social justice through their advocacy. This study examines the persuasive impact of athlete advocacy on individual cognitive responses about racial discrimination from a causality perspective. Research methods This study employed survey experiments, specifically randomized controlled trials based on questionnaire surveys, within the context of Japanese athletes’ racial advocacy. Two original experiments were performed with 2,251 Japanese adults recruited from an online panel, using treatments with information on athlete advocacy as the intervention. Results and Findings The findings highlight that exposure to athlete racial advocacy can slightly facilitate individuals’ cognitive responses about racial issues, yet its persuasive power is fairly limited. Using multiple treatments that manipulated the fit between advocate athlete and advocacy content, our data also present experimental evidence that the persuasive power of athlete racial advocacy remains consistent across advocates’ racial backgrounds. Implications This study provides empirical and causal evidence of the persuasive power of athlete advocacy. Our findings contribute to the literature on the influence of athletes as advocates and sport for social justice.