Muhammad Ali today paid tribute to his great rival Joe Frazier, saying: “The world has lost a great champion.”
Frazier, who had been suffering from liver cancer, died overnight at the age of 67, his family confirmed in a statement.
This morning tributes poured in from throughout the world of boxing and beyond.
But it is his fights with Ali for which Frazier is best remembered.
Frazier beat Ali on points in the so-called ‘Fight of the Century' in 1971, but lost in two further meetings including the epic ‘Thrilla in Manila' in 1975.
Today Ali said: “The world has lost a great champion. I will always remember Joe with respect and admiration.
“My sympathy goes out to his family and loved ones.”
The pair had an at-times fraught relationship, dating back to taunts Ali directed at his rival in the build-up to their famous trilogy of fights.
But they were reported to have been on better terms in recent years.
Boxing stars of a more recent era took to Twitter to share their thoughts, with Floyd Mayweather writing: “RIP Smokin Joe. My thoughts and prayers go out to to the Frazier family. We lost an all time great tonight.”
The fighter known as ‘Money' continued: “My Condolences go out to the family of the late great Joe Frazier. £TheMoneyTeam will pay for his Funeral services.”
Oscar De La Hoya wrote simply: “I will miss you my friend. R.I.P. Joe Frazier”, while Shane Mosley added: “Joe Frazier one of the greatest heavy weight champions ever. RIP.”
Promoter Frank Warren believes his fights with Ali and George Foreman mean Frazier will be remembered as one of the sport's greats.
Warren said: “He was part of that era of the best heavyweights there have ever been.
“The trilogy of fights that he had with Muhammad Ali, the tough fight he had with George Foreman and the good wins on the way — he was one of the most exciting heavyweights ever.
“People talk about Mike Tyson at the age of 21 — Joe Frazier, when he was a young fella, was every bit as good as, if not better than, Mike Tyson.”
Joe Bugner, another pre-eminent fighter of the era widely considered to be the greatest in boxing history, lost to Frazier five months after being beaten by Ali in 1973.
But it was the fight against Frazier, who visited Bugner in Australia for his 60th birthday last year, which the Hungary-born fighter felt was a turning point in his career.
“Joe Frazier was relentless,” Bugner said. “Here was a man about 5ft 10, he weighed about a stone lighter than myself, but he was so courageous and ferocious, you had to literally hit him with a sledgehammer to put him away.
“It hit me like a lightning bolt when I heard he died.”
British former heavyweight champion Lennox Lewis added: “He definitely was legendary and he made a great contribution to boxing.
“I'm so sad for his family. Nobody likes to hear about great heroes passing on. It's very sad for boxing today.”