Gwynn attended college at San Diego State University (SDSU), where he played both college baseball and college basketball for the San Diego State Aztecs. He was selected by the Padres in the third round of the 1981 Major League Baseball Draft as the 7th overall pick. Gwynn played in the only two World Series appearances in San Diego’s franchise history. He had a .338 career batting average and never hit below .309 in any full season. Gwynn accumulated 3,141 career hits as a contact hitter. His jersey number 19 was retired by the Padres in 2004. He was head baseball coach for San Diego State University at the time of his death at the age of 54.
Gwynn died on June 16, 2014 after battling salivary gland cancer.