Thomas B. Edlefsen (born December 12, 1941) is a former professional tennis player from the United States.

Edlefsen was a member of three NCAA Championship winning teams while at the University of Southern California, in 1963, 1964 and 1966.

[1] At the U.S. National Indoors in 1964, Edlefsen had wins over both Arthur Ashe and Roy Emerson.

[2] In 1967, he developed a nerve disease, Guillain–Barré syndrome, after suffering a reaction to a smallpox vaccination he had while with the Air Force Reserves.

[3] He recovered after six months in hospital and returned to tennis, notably making the fourth round at the 1968 Wimbledon Championships, along the way defeating 14th seed Cliff Drysdale.