Norton started boxing in the United States Marine Corps and turned professional after his discharge in 1967.
In 1973 he broke Ali's jaw during their first fight, claiming the North American Boxing Federation heavyweight title in a split decision over 12 rounds.
Ali's camp said his jaw broke early in the fight, but Norton told a Reuters correspondent at a boxing convention inCancun, Mexico, more than three decades later, that a punch thrown in the 11th round caused the fracture.
Ali narrowly won a split decision in a rematch nearly six months later and held on to his heavyweight title in a bruising third encounter in 1976.
Norton retired from the ring in 1981, ending his career with 42 wins, seven losses and a drawl he had 33 knockouts.
The former boxer then became a commentator and actor.