Background: Rotator cuff repair is widely recognized as one of the most painful orthopedic surgeries, yet postoperative pain management in these patients is often underexplored. This study aimed to explore the relationship between pain outcomes and functional recovery six months after arthroscopic rotator cuff repair (ARCR), with a focus on the role of different pain coping mechanisms as mediators. Methods: This study included 83 patients that underwent rotator cuff repair. Pain levels were assessed using the Brief Pain Inventory (BPI-SF), while shoulder function was evaluated using the Oxford Shoulder Score (OSS). Coping strategies, including self-statements, ignoring pain, distraction, and praying, were examined in relation to pain severity and interference and were assessed with the Coping Strategies Questionnaire-Revised (CSQ-R). Simple and parallel mediation analyses were performed using the PROCESS macro to assess the mediating effects of coping mechanisms on the relationship between pain intensity, pain interference, and postoperative OSS. Results: Post-surgery, patients showed a significant improvement in OSS (from 29 ± 9 to 42 ± 6). At six months, 24% of patients reported chronic postsurgical pain (CPSP), defined as a pain severity score of 3 or higher. Correlation analyses revealed that OSS was negatively associated with pain catastrophizing (r = −0.35, p < 0.01) and praying (r = −0.28, p < 0.01). OSS was significantly negatively associated with pain severity (r = −0.54; p < 0.01) and pain interference (r = −0.51, p < 0.01). Mediation analysis demonstrated that coping self-statements significantly mediated the relationship between pain interference and shoulder function (a*b = 0.5266 (BootSE = 0.2691, 95% CI [0.1010, 1.1470]), emphasizing the important role of cognitive strategies in supporting recovery outcomes. Conclusions: Patients engaging in adaptive coping strategies, particularly coping self-statements, reported better functional outcomes. The findings underscore the importance of targeted interventions focusing on effective pain coping mechanisms to improve recovery post-ARCR.