Former heavyweight champ Joe Frazier critically ill with liver cancer

One of the most feared knockout boxers in the history of boxing, Joe Frazier, is now facing an opponent within his own body - liver cancer.

According to the N.Y. Post's Kevin Kernan, the 67-year-old Frazier is battling advanced stages of liver cancer.

"He's in serious shape, we're looking for a miracle," said a source close to the former heavyweight champ. "They're only giving him a short time to live. We need to have as many people as possible praying for Joe right now."

According to Leslie Wolff, Joe Frazier's personal and business manager, the former heavyweight fighter was diagnosed four or five weeks ago, but hasn't been told how long he has to live.

According to AP, Wolff said "We have medical experts looking into all the options that are out there, there are very few. But that doesn't mean we're going to stop looking."

Frazeir and Ali

Frazier will always be linked to Muhammad Ali for their series of fights between 1971-1975.

Their first meeting was dubbed "The Fight of the Century" which came in 1971 at New York's Madison Square Garden when both fighters were unbeaten. They earned a record sum of $2.5 million each. The lead up to fight had a good vs. evil feel.

For the fans, either Frazier or Ali filled the role. Frazier won a one-sided decision (11-4, 9-6 and 8-6) handing Ali his first career loss. He floored Ali in the 15th round.

Ali took the 1974 rematch at MSG via majority decision.

The "Thrilla in Manila" closed out the trilogy. In 1999, ESPN's SportsCentury named the bout the fifth greatest sporting event of the 20th century. Ali won the fight, Frazier could barely see after 14 rounds so his trainer Eddie Futch stopped the bout to save his fighter from further damage.

Frazier retired with one final fight in 1981 with a career mark of 32 wins and 4 losses with 27KO's.

Frazier has always been regarded as a gentleman.

Frazier is the son of a South Carolina sharecropper, he was on the 1964 Olympic team and won a gold medal. Over his boxing career, he won 32 fights, 27 by knockout. He had four losses and one draw. He won his first eleven fights by knock out. In 1968, he beat Buster Mathis for the New York State world title at Madison Square Garden. He made six title defenses after that over the next several years.

He was most recently seen in Las Vegas during the Floyd Mayweather-Victor Ortiz fight. He participated in a series of autograph signings.