Gwynn was a two-sport star with San Diego State, playing three seasons of baseball and four of basketball. He was a two-time All-American outfielder in his final two seasons, when he led the team in hitting. A skilled playmaker in basketball, he set multiple school records for assists. He is the only player in the history of the WAC to earn all-conference honors in two sports. Gwynn was not allowed to play baseball as a freshman. He was overweight at , and Vezie wanted him to get in shape for the next basketball season.