Who is the only professional boxer to have fought Muhammad Ali, Larry Holmes, and Mike Tyson?

Trevor Berbick is the only man in professional boxing history to have fought Muhammad Ali, Larry Holmes, and Mike Tyson.

Trevor Berbick (1 August 1954 – 28 October 2006) was a Jamaican professional boxer who competed from 1976 to 2000. He won the World Boxing Council (WBC) heavyweight title in 1986 by defeating Pinklon Thomas, then lost it in his first defense in the same year to Mike Tyson.

A 1980 upset of ex-champ John Tate (9th-round KO) secured a title shot against Larry Holmes on 11 April 1981, but Berbick lost a 15-round unanimous decision. In his second fight after the loss, he beat 39-year-old Muhammad Ali by unanimous decision in the final fight of Ali's career.

As an amateur, Berbick won a bronze medal in the heavyweight division at the 1975 Pan American Games. In both his early and late professional career he held the Canadian heavyweight title twice, from 1979 to 1986 and 1999 to 2001.