George Louis Chuvalo is a Canadian former professional boxer who was a five-time Canadian heavyweight champion and two-time world heavyweight title challenger. He is known for having never been knocked down in his 93 bout professional career including fights against Muhammad Ali, Joe Frazier, and George Foreman. Chuvalo unsuccessfully challenged Muhammad Ali for the heavyweight championship in 1966. Chuvalo was inducted into the Ontario Sports Hall of Fame in 1995.

Muhammad Ali was an American professional boxer and activist. Nicknamed "the Greatest", he is regarded as one of the most significant sports figures of the 20th century and is often regarded as the greatest heavyweight boxer of all time. He held the Ring magazine heavyweight title from 1964 to 1970. He was the undisputed champion from 1974 to 1978 and the WBA and Ring heavyweight champion from 1978 to 1979. In 1999, he was named Sportsman of the Century by Sports Illustrated and the Sports Personality of the Century by the BBC.