Athletes often experience pain during their sport performances and in their everyday lives (Spencer, 2012). However, there is little research that has explored how athletes form understandings of pain, and how social interactions contribute to athletes' understandings of pain. The purpose of this study was to explore mixed martial artists' experiences of pain while training for a MMA competition. Specifically, this research examined the meanings that fighters attribute to their pain experiences and how teammate and coach relationships contributed to fighters' experiences of pain. A multiple case study approach (Stake, 1995) was used to study pain among four amateur and professional mixed martial artists and their training partners (total N = 7). Data were collected over four months from the beginning of a training camp to the completion of a fight, using semi-structured interviews, participant observation, athlete video diaries, and video recordings of training sessions and fights. Data were analyzed using interpretative phenomenological analysis (Smith, Flowers, & Larkin, 2009). Results pertained to: (a) conceptualization and distinctions between physical pain, injury, and emotional pain; (b) the process of giving and receiving pain for fighters (e.g., pain built connections/trust between teammates); and (c) how teammates enabled fighters to move through their pain experiences. These findings are discussed with respect to fighters' relationships with pain (e.g., bringing self-awareness and attention to vulnerabilities) and how pain 'callused' or toughened fighters physically and emotionally. The researcher will also discuss implications for pain research in sport, and the use of video diaries in qualitative research.