Muhammad Ali today led the tributes to Smokin' Joe Frazier, one of the greatest world champion heavyweight boxers, who has died from liver cancer at the age of 67.Frazier famously ended Ali's unbeaten record as a professional in New York in 1971, lost a rematch in 1974, and was again defeated by his rival in 1975 in the famous 'Thrilla In Manila', an encounter still regarded as one of the most brutal in boxing history.The rivalry between Frazier and Ali was intense and was tainted by the insults spat by the 'Louisville Lip'. But today, Ali insisted: «I will always remember Joe with respect and admiration. The world has lost a great champion.