Behind on all three officials cards, Rocky Marciano knocks out champion Jersey Joe Walcott in the 13th round to win the heavyweight title in Philadelphia.
In his last fight, Rocky Marciano KOs light-heavyweight champion Archie Moore in the ninth round in New York and finishes with a 49-0 record, the only heavyweight champion to end his career unbeaten.
At 32, Rocky Marciano retires as boxing's only undefeated heavyweight champion (49-0).
Mike Tyson knocks out his 17th straight opponent, Mike Jameson, to break Rocky Marciano's heavyweight record for consecutive KOs at the start of a career.
Rocky Marciano is the only heavyweight champ to retire undefeated (49-0). SportsCentury: Rocky Marciano airs Tuesday at 4 pm ET.