Like many of his contemporaries from boxing's golden era of the 1970s, Ron Lyle, who has died aged 70 from complications following stomach surgery, could have been forgiven for looking at the state of modern heavyweight boxing and drawing the conclusion that he was born 40 years too early. It was his misfortune that he had to fight Muhammad Ali in his only shot at the world heavyweight title, in Las Vegas in May 1975, a contest he lost when he was stopped in the 11th round. It is not overstating Lyle's abilities to say that he would probably have been a champion had he fought many of the title holders who followed in the decades thereafter.

The big-punching Lyle had been ahead on all three judges' cards against a lethargic looking Ali before the champion unleashed a terrific right hand to the head and landed around 30 more unanswered blows to prompt the referee to call the fight off. Lyle would always argue that the fight had been stopped prematurely, saying: "I felt I was robbed of the greatest honour in all sport." He later added in a 2009 documentary about Ali: "Am I bitter? Forget about it. I never took it personal. If [it wasn't] Ali, you think you would be sitting here talking to Ron Lyle? About what?"

Born in Dayton, Ohio, he was one of 19 children born to William and Nellie Lyle. He came to boxing late, after being jailed as a teenager for second degree murder in a gang fight. Standing 6ft 3in and weighing around 15 stone, Lyle was an athletic and intimidating figure who said he was capable of doing 1,000 press-ups in an hour. Initially, while in Colorado State Penitentiary, trouble followed him. He was stabbed in the abdomen by another inmate and twice pronounced dead on the operating table during surgery. According to Lyle, one doctor signed his death certificate. "They had to give me, like, 36 blood transfusions," he told Howard Cosell. "I was on the operating table about 10 o'clock that morning, and I didn't get off until about 5.30 that evening."

Later he would credit the prison's athletic director with giving his life purpose and discipline by getting him interested in boxing, a sport at which he quickly excelled. He claimed to have never lost a prison fight after being defeated in his first bout. Despite being sentenced to serve 15-25 years, he was paroled in 1969 at the age of 28. He quickly determined to make something of his life as a boxer. Blasting his way through most of his opponents in his 29 fights as an amateur, it was clear Lyle had a future as a professional. At 30, he fought in the paid ranks for the first time and quickly became a contender.

He suffered points losses against the highly rated Jerry Quarry in 1973 and Jimmy Young in 1975, three months before his fight with Ali, but Lyle also scored impressive wins over the former champion Jimmy Ellis, Buster Mathis and the tough Argentinian Oscar Bonavena before his challenge for the title.

An epic struggle with the former champion George Foreman in 1976 was Lyle's reward for a knockout victory over the feared puncher Earnie Shavers. Foreman was returning to boxing after shockingly losing the world title to Ali in Zaire in 1974. Both Foreman and Lyle were down twice before Foreman knocked him out in the fifth round.

A split decision win over Britain's Joe Bugner in 1977 was among his later triumphs, but Lyle was a declining force by the time he retired in 1980, aged 39, after losing inside a round to the much-hyped prospect Gerry Cooney. Hoping to face Foreman for a second time for the title, after Big George had regained it in 1994, Lyle made an unlikely comeback at the age of 54. He won four contests in 1995 against lowly rated club fighters, but the Foreman dream never materialised and Lyle retired for good having won 43 fights, lost seven and drawn one.

Lyle, who worked as a security guard and a trainer in his later years, was again accused of murder in 1978, after a fellow prison inmate was shot at Lyle's home. Lyle claimed self defence and was acquitted. A biography of Lyle, Off the Ropes: The Ron Lyle Story by Candace Toft, was published in 2010.

Lyle was divorced from his wife, Nadine.

• Ron Lyle, boxer, born 12 February 1941; died 26 November 2011