After winning a silver medal in the 1,500 m freestyle at the 1971 Pan American Games, Tom McBreen set a world record in the 400 m free later in the month. He was also a member of two world record breaking teams in the 800 m freestyle relay in 1970 (with Gary Hall, John Kinsella, and the non-Olympian Mark Lambert) and 1971 (with Jerry Heidenreich, Mark Spitz, and Fred Tyler). McBreen, who swam for Southern Cal and the Golden Gate SC, won the AAU outdoor 400 m freestyle in 1971 and 1972. All his records and championships were won despite being legally blind in both eyes, and having suffered several minor injuries – all to his right side – during his swim career. McBreen later went to medical school and specialized in family medicine.