Jack Underhill dominated the sport of badminton in Canada between 1925 and 1947, winning numerous provincial and national championships. He was once described as a “brilliant defensive and opportunistic player with the stamina of an ox.” Underhill often competed in mixed doubles events with his wife, Eileen, also a BC Sports Hall of Famer. As well as badminton, he played tennis, rugby on the UBC and VRCteams, and squash.

Underhill won the BC junior championships three consecutive years from 1916-18. He was a five-time BC singles champion winning in 1927-1929, 1931, and 1935 and a nine-time BC mixed doubles champion. In 1928-31 and 1935, he won the title with his wife, Eileen.

Underhill won the Canadian singles championship in 1928 and 1932 and was Canadian doubles champion five times in 1925, 1927, 1932, 1936, and 1947—each time with a different partner. He participated in an exhibition tournament and won the All-England world championship in 1930 by a score of 15-10, 15-9. In 1949, he won the doubles event in the All-India vs. Vancouver match with partner and fellow BC Sports Hall of Famer Johnny Samis.

After retiring from competition, Underhill served badminton in several executive capacities, including acting as president of the Vancouver, BC and Canadian Badminton Associations.