1954: Muhammad Ali at age 12
Getty ImagesAli—then known by his birth name, Cassius Clay—began boxing in his hometown of Louisville, Kentucky, in 1954 because he wanted to fight a thief who had stolen his bicycle. “Well, you better learn how to fight before you start challenging people you’re going to whup,” police officer Joe Martin told young Clay. The aspiring pugilist trained with Martin and won his first amateur bout later that year.
September 1960 vs. Zbigniew Pietrzykowski
Getty ImagesA teenage Clay nearly didn’t go to the 1960 Olympic Games in Rome because he was afraid of the flight. According to the Muhammad Ali Center, he’s believed to have worn a parachute for the entire plane ride. Once on land again, there was no stopping him. Clay beat Poland’s Zbigniew Pietrzykowski in the final bout to win a gold medal for the United States.
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May 1965 vs. Sonny Liston
John Rooney//APAfter dethroning Sonny Liston as heavyweight champion in 1964, the same year Ali changed his name to reflect his Nation of Islam membership, the challengers squared up for a rematch in Lewiston, Maine. The fight lasted less than 2 minutes, as Ali knocked out Liston with a “phantom punch” that very few in the audience could even see. Their gloves from the bout sold for almost $1 million at auction in 2015.
Read More: Inside the Ali-Liston Rematch
March 1966 vs. George Chuvalo
Getty ImagesGeorge Chuvalo, a Canadian challenger, battled the champ a full 15 rounds. Ultimately, Ali won by unanimous decision to retain his heavyweight title. The pair had a rematch in May 1972, which again resulted in victory for Ali.
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November 1966 vs. Cleveland Williams
Getty ImagesAccording to ESPN, more than 35,000 fans—then an indoor record—crowded into the Houston Astrodome for Ali’s seventh title defense, this time against hometown favorite Cleveland Williams. However, they all went home early after Ali knocked out Williams, known as the “Big Cat,” in the third round.
December 1970 vs. Oscar Bonavena
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March 1971 vs. Joe Frazier
Getty ImagesOctober 1974 vs. George Foreman
Getty ImagesAli was an underdog against then-undefeated George Foreman in their showdown in Kinshasa, Zaire (now the Democratic Republic of the Congo). The fight is famously known as the “Rumble in the Jungle.” In this photo, Ali is utilizing his rope-a-dope technique, leaning against the ring ropes to help absorb punches. The strategy worked, as Ali eventually won via eighth-round knockout.
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October 1975 vs. Joe Frazier
Getty ImagesAli already claimed a non-title rematch against Frazier in 1974, setting up their third and final bout in the Philippines: the “Thrilla in Manila.” The bout was one of the most brutal in the sport’s history, with Ali remarking it was the “closest thing to dyin’ I know of.” With his fighter already battling limited eyesight because of a cataract, trainer Eddie Futch pulled Frazier from the match after the 14th round, giving Ali a knockout win.
September 1977 vs. Earnie Shavers
Getty ImagesAli was on a 13-match win streak and still heavyweight champion as he entered his match with Earnie Shavers. Little did those at Madison Square Garden know it would be his final successful title defense, with Ali winning by unanimous decision.
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September 1978 vs. Leon Spinks
Getty ImagesAli’s final career win came in a rematch with Leon Spinks, to whom he had dropped the heavyweight title only seven months prior in a split decision. Held at the Superdome in New Orleans, the bout set another indoor attendance record for boxing. Ali prevailed by unanimous decision. Even after announcing his retirement in July 1979, he would enter the ring two more times.
December 1981 vs. Trevor Berbick
Getty ImagesAli, then 39, faced 27-year-old Trevor Berbick in his final professional match, held in Nassau, Bahamas. Berbick won by unanimous decision, leaving Ali with an all-time record of 56-5-0. Berbick became heavyweight champion in 1986 but quickly lost the title to a rising star among boxers: 20-year-old Mike Tyson.

Tyler Piccotti joined the Biography.com staff as an Associate News Editor and is now the News and Culture Editor. He previously worked as a reporter and copy editor for a daily newspaper recognized by the Associated Press Sports Editors. In his current role, he shares the true stories behind your favorite movies and TV shows and profiles rising musicians, actors, and athletes. When he's not working, you can find him at the nearest amusement park or movie theater and cheering on his favorite teams.
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