Sport is a widespread phenomenon across human cultures and history. Unfortunately, positive emotions in sport have been long vaguely characterized as happy or pleasant, or ignored altogether. Recent emotion research has taken a differentiated approach, however, suggesting there are distinct positive emotions with diverse implications for behavior. The present study applied this evolutionarily informed approach in the context of sport to examine which positive emotions are associated with play. It was hypothesized that pride, amusement, and enthusiasm, but not contentment or awe, would increase in Ultimate Frisbee players during a practice scrimmage. Further, it was hypothesized that increases in pride and amusement during practice would be differentially associated with sport outcomes, including performance (scores, assists, and defenses), subjective social connectedness, attributions of success, and attitudes toward the importance of practice. It was found that all positive emotions decreased during practice. It was also found that increases in pride were associated with more scores and greater social connectedness, whereas increases in amusement were associated with more assists. The present study was one of the first to examine change in positive emotions during play and to relate them to specific performance outcomes. Future studies should expand to determine which came first: emotion or performance.