Boxing greats paid their respects to one of the best heavyweights of all time Monday as Joe Frazier was laid to rest at Enon Tabernacle Baptist Church in Philadelphia.

Frazier, who moved to Philadelphia as a teenager from South Carolina, died last week after a short battle with liver cancer. He was 67. 

Roughly 4,000 people showed up to honor Smokin' Joe. His great rival Muhammad Ali, a name that will forever be tied with Frazier, was in attendance at the funeral, as were Larry Holmes, Michael Spinks and Bernard Hopkins, along with famed promoter Don King.

Frazier's greatest victory was the unanimous decision victory after 15 rounds against Ali in 1971's Fight of the Century at Madison Square Garden.

He would go on to lose two fights to Ali, including the famed Thrilla in Manilla in the Philippines. In Saturday's Manny Pacquiao-Juan Manuel Marquez in Las Vegas, there was a 10-bell salute for Frazier, a fitting tribute considering how momentous the fight in the Philippines was, and with the most-famed Filipino boxer ever about to go into a trilogy bout of his own. 

The Rev. Jesse Jackson delivered Frazier's eulogy, and described him as a man who came from segregation, degradation and disgrace to amazing grace. 

Mike Tyson, Donald Trump and the actor Mickey Rourke sent recorded messages of condolences. George Foreman, who defeated Frazier twice, didn't attend the funeral because it would be too much for him, he said.

"I loved this one," said Foreman, according to ESPN.

"Frazier was more than a boxer, he was an icon. The winner of a gold medal in the 1964 Olympics, the Philadelphia sports legend went on to win his first 29 professional fights. He was a boxer who fought with grit and determination, and embodied his blue-collar upbringing. His left hook was one of the great knockout tools in history of the sport."

In an exclusive interview with International Business Times, famed boxing historian and expert Bert Sugar described Frazier as a dear friend, who was open and simple, and didn't show a hint of insincerity. He said Frazier was incapable of handling Ali's racially charged taunts and didn't understand his role with Ali against the backdrop of the Vietnam War.

Sugar, who believes Frazier was never fully appreciated, said it is only now that he getting his due respect, and recalled a recent moment he shared with Frazier that was particularly touching.

"I remember sitting with him, just the two of us, I think it was at the New York Athletic Club, and he was scratching, itching, clawing at his hand,' said Sugar. I said, 'Joe, what's the matter?' And he said, sorrowfully, 'I don't know why he sang I was an Uncle Tom. I'm darker than he is.' You make a judgment on that. I know what it means."

Sugar, who said his major accomplishment was getting Frazier to wear hats, concluded his tribute to Frazier with a somber message of a great boxer who deserved more than he received.

"He played a second fiddle all his life to Muhammad Ali, and that was unfair to Joe Frazier," said Sugar. "He was one hell of a fighter, and one hell of a man."

Enclosed are clips from Joe Frazier's funeral and his boxing career.