Since 2012, Donald "Don" Gomsi has served as a tennis instructor with at Carmel Valley Tennis in Del Mar, California. In this position, he draws on several decades of experience teaching tennis at all levels while monitoring and managing club operations. Prior to taking on his current role at Carmel Valley Tennis, he spent four years as a tennis teaching professional at the Barnes Tennis Center in San Diego. In addition to his work as an instructor, Don Gomsi has worked with the United States Professional Tennis Association (USPTA) as a head tester since 1985. He served as the California head tester until 1997. In 2000, he joined the organization's San Diego division.
While studying environmental health at San Diego State University, Donald Gomsi spent four years on the school's varsity tennis team. He continued at the university in a master of science program while competing in tournaments and teaching at a nearby tennis club, earning his degree in biology in 1983.