Former heavyweight champion of the world Joe Frazier has died, just days after his family announced that he was suffering from liver cancer. He passed away in his home town of Philadelphia.

"Smokin' Joe" held the WBC and WBA championship belts from 1970 to 1973, when he lost the title to George Foreman. His brawling, hard-hitting style made him one of the most popular fighters of his era, as he regularly knocked out much bigger heavyweights. (Some fans had even offered to give Frazier portions of their liver for a transplant after learning of his illness.) He retired in 1976 after a second loss to Foreman.

Of course, Frazier will forever be linked with Muhammad Ali, thanks to their three epic fights that formed the most legendary rivalry in boxing history. Frazier handed Ali his first defeat ever in 1971 (Ali had been stripped of his title after resisting the draft during Vietnam.) Frazier would lose the rematch in a 12-round decision in 1974 and a year later, lost "The Thrilla in Manilla," after his trainer threw in the towel before the 15th round. The third fight is considered by some fans to be the greatest bout of all time. The three brutal fights took a tremendous toll on both men — they were both hospitalized after the first match — and were also marked by vicious trash talking from Ali, who called Frazier a gorilla and an Uncle Tom. 

Frazier finished his career with 32-4 record, with all four losses to coming to champions Ali and Foreman. (A brief comeback in 1981 resulted in a single draw.) He also won a gold medal at the 1964 Olympics.