Muhammad Ali throws a left at Joe Frazier during their memorable first fight at New York’s Madison Square Garden on March 8, 1971. (John Lindsay/AP Photo)

It had been more than 40 years since the fight — the fight — and the years had clearly taken their toll on the brave and courageous former champion. He’d just finished signing autographs to make a few extra bucks in the opulent lobby of a Las Vegas hotel where in a few days, much of the boxing world would convene to watch the latest incarnation of The Fight of the Century.

He saw a familiar face, and struggled to pull his body out of a folding chair to say hello. Asked about the fight that weekend, Joe Frazier declined to give an opinion. He gave a reporter a bear hug and a pat on the back.

He beamed and in a slow drawl, he said, “Man, we had the whole world watching us. The whole damn world!”

Frazier was only months from the end that day and had a weariness about him that was the antithesis of his younger self. In the ring, Frazier was a relentless buzzsaw, always pressing forward, in perpetual motion as he sized up his foe. He was an irresistible force who would impose his will upon some of the meanest, toughest and best boxers who ever lived.

He would do it again on March 8, 1971, in what is arguably the most significant sporting event in the history of this country. It was on that day at Madison Square Garden in New York 48 years ago that Frazier, an undefeated fighter with a legitimate claim to the heavyweight title, faced another man with a similar claim.

By 1971, Muhammad Ali was one of the most recognizable faces on Earth. He’d been stripped of his championship in 1967 for refusing induction into the military as a conscientious objector to the Vietnam War.

He lost his boxing license and was forced to sit out the final nine months of 1967, all of 1968 and 1969 and the first nine-plus months of 1970 before he returned to spectacularly take out Jerry Quarry in Atlanta on Oct. 26, 1970.

Ali stopped Quarry in the third round after three years and seven months out of the ring. He would come back 42 days later to stop Oscar Bonavena in the 15th round.

That led to the fight that literally stopped the sporting world.

Nothing was bigger. Frank Sinatra served as a ringside photographer while Burt Lancaster, who at that point had won the Academy Award for Best Actor three times, was on the broadcast team.

The crowd was filled with movie stars and musicians, athletes and politicians. Gene Kelly, Woody Allen and Ed Sullivan were there. So, too, was Sugar Ray Robinson, the greatest fighter who ever lived, as were ex-heavyweight champions Joe Louis and Jack Dempsey, former Vice President Hubert Humphrey and Sen. Edward M. Kennedy.

The fight would prove to be performance art at the highest level, the boxer versus the slugger, the fast, athletic and braggadocious challenger against the indefatigable champ whose punches were so hard and sharp it seemed as if he could make the walls of a building quake.

It was a magnificent ballad of violence, Ali continually circling and popping the blazing jab, dropping a right hand when Frazier managed to box him into a corner. Frazier chugged relentlessly forward, bobbing left, weaving right, his arms in front of his face to try to protect against Ali’s rapier-like jabs.

All the while, Frazier was willing to take one, or even two or three, if only he could get off that left hook. He believed in his left hook unequivocally, and in the 15th round, in perhaps the most famous punch in boxing history, he leaped and landed it on Ali’s chin.

The challenger went down with a minute left in the fight, and clearly was in trouble. It had been obvious to any neutral observer by that point that Frazier would win the fight, but this knockdown would punctuate it.

Frazier went on to win a unanimous decision, but the aftermath was almost a nightmare. Ali boasted that he put Frazier in the hospital, and that he was largely unmarked.

In the ensuing years, Ali’s popularity and legend grew, and he never let up the attack on his rival. Bob Arum, whose career in boxing began in 1966 when he promoted an Ali bout in Toronto against George Chuvalo, was close to both men.

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