Concannon was a three-year starter as a shortstop for coach Jack Barry's baseball teams and he captained the 1952 NCAA Baseball Championship team. During that season he went on a defensive streak that saw him handle 85 plays without an error and only had two errors for the season. Concannon had a career batting average of .273, as he was a contact hitter who batted fourth in the lineup. In a game against Yale on June 5, 1952, he drove in five runs while going 3 for 5 and playing errorless ball at shortstop. An All-New England selection in his senior season, Concannon was drafted by the Boston Braves and played professionally. He became a lawyer and was appointed a judge in later years.