Gillespie won the McKelvin Award as the top all-around athlete in the Southern Conference for the 1947-48 academic year. Gillespie, former Tiger pitcher Kris Benson and former Clemson quarterback Deshaun Watson are the only Clemson athletes named a conference athlete of the year in school history.
Gillespie was the last Clemson athlete to letter in the three major sports of football basketball and baseball. The native of West Virginia lettered in baseball in 1943 before spending three years in the Army. After returning to Clemson, he was a starting guard on the Tiger football team for three years. He was also a starting guard in basketball for three years, and played three more years of baseball, where he made the All-State team as a senior.
Gillespie double-majored in electrical engineering and textile engineering and served as president of his senior class. An honor student, he was inducted into the Clemson Hall of Fame in 1977.