This case study outlines the sport psychology service delivery provided to a 17-year-old international-level competitive figure skater. The client had a diagnosis for autism spectrum disorder and reported experiencing low self-confidence, which hindered his performance in training and competition. An acceptance and commitment therapy intervention was implemented over 25 sessions across a 15-month period. The aim of the intervention was to develop self-confidence by encouraging acceptance of unhelpful thoughts, rather than changing or removing them, to move the client toward the athlete he wanted to be. This case offers a novel contribution to the wider literature by reporting an acceptance and commitment therapy intervention to develop self-confidence in sport. We report how psychological flexibility was achieved through exercises to “unhook” the client from his thoughts around perfection and self-imposed pressure. Reflections from the client and practitioner capture the evaluation of the service delivery process.