World heavyweight boxing champion in the 1970s who famously broke the jaw of Muhammad Ali in the first of their three fights
The former world heavyweight boxing champion Ken Norton, who has died aged 70 after a long period of illness, will be best remembered for breaking Muhammad Ali's jaw on his way to a points victory in the first of their trilogy of heavyweight fights. He lost the next two encounters with "The Greatest" narrowly and contentiously; many believed Norton should have been awarded the decision in all three contests.
Norton, a former US marine, had a cross-armed defensive style that troubled Ali. Superbly conditioned, with a chiselled muscular physique that made him sought after in Hollywood – his films included Mandingo (1975), with Susan George, and Drum (1976), with Pam Grier – he was a lightly considered underdog when he first fought Ali in 1973.
Gene Kilroy, who acted as Ali's business manager, said: "Ali thought it would be an easy fight. But Norton was unorthodox. Instead of jabbing from above like most fighters, he would put his hand down and jab up at Ali." Ali was never able to get into his familiar rhythm, and was on the receiving end of a split points decision after 12 rounds. He was left in hospital, where his broken jaw had to be wired up.
Picked as a supposedly soft touch, Norton had been offered $50,000 for the fight. "For $50,000, I'd fight the Russian army," he said. ABC's commentator Howard Cosell had said before the fight that it was "the worst mismatch in boxing history and a disgrace". Later he said: "Kenny, you made me look silly." Norton replied: "That's OK, Howard, you always look silly."
Six months later, Norton and Ali fought again and this time Ali prevailed by a split decision, setting up a decider in 1976 at the Yankee stadium in New York. By then, Ali was world champion and generating huge sums of money wherever and whenever he fought. The judges gave a narrow points decision against Norton, with booing greeting the verdict from many in the 30,000 crowd.
Norton was born and brought up in Jacksonville, Illinois. His father, John Norton, was a fire service engineer; his mother, Ruth, was a hospital therapist. An outstanding all-round athlete, Norton won a scholarship to Northeast Missouri State College (now Truman State University) through his proficiency at basketball and American football and as a track athlete. It was only after enlisting in the marine corps that he began boxing, quickly finding that his strength and physique – he stood 191cm (6ft 3in) and weighed about 100kg (220lb) – made him ideally suited to the sport.
Norton was the All-Marine heavyweight champion three times before turning professional in 1967. He made the usual advance of a heavyweight prospect, repelling a succession of the sport's journeymen and soon gained respect in the division. He boosted his earnings with sparring work against the likes of Joe Frazier, with whom he shared a trainer in Eddie Futch.
Frazier, who was close to Norton as a friend, never fought him. But Norton did fight another great heavyweight of the 1970s, George Foreman, for the title in 1974. At the peak of his powers, Foreman faced Norton in Caracas, Venezuela, and floored him three times before the stoppage came in the second round, enabling Foreman to dramatically retain the title he had won by defeating Frazier in 1973. Foreman would later become friends with Norton and praised him, saying: "He fought Ali through all those questionable decisions and, even though he was patriotic [Ali had famously refused to serve in the army], he never used that against Ali. That made me so proud of him. He was humane."
Despite the bitter disappointment of losing to Ali in their third fight, Norton rebounded with three wins in 1977 – including victories over the highly rated Duane Bobick and Jimmy Young – and earned himself the position of mandatory challenger for the title, which was claimed by Leon Spinks after his shock victory over Ali in February 1978. The World Boxing Council awarded Norton the title when Spinks agreed to a rematch with the ageing Ali instead of a fight against Norton.
Norton lost his title in his first defence as champion, again suffering the agonies of being on the wrong end of a split decision, when he took on Larry Holmes in what is now recognised as one of the all-time classic world heavyweight fights. For 15 rounds at Caesars Palace, Las Vegas, the two men traded power punches of almost frightening intensity. Holmes would go on to be recognised as the world No 1 until the mid-1980s, while Norton was never the same fighter again.
A loss to the big-punching Earnie Shavers in 1979, with Norton suffering a first-round knockout, suggested his time had gone. Another first-round stoppage, against Gerry Cooney in 1981, prompted Norton to announce his retirement from the sport.
In 1986, a car accident almost killed Norton. He suffered multiple injuries, including a fractured skull and a brain injury that left him with slurred speech. Before then, he had been working as a ringside commentator and had continued to act in films and on television. After a long period of declining health, including a succession of strokes and a heart attack, he moved into a care home.
Norton is survived by his wife, Rose, and his children Ken (an American football linebacker who now coaches with the Seattle Seahawks), Keith, Kenejon and Kenisha.
• Kenneth Howard Norton, boxer, born 9 August 1943; died 18 September 2013
• This article was updated on 20 September 2013. The original stated that Mandingo starred Joan Collins. This has been corrected.