1. Cleveland Williams, third-round knockout, Houston 1966: Ali was at his devastating best against one of the hardest hitters in the sport’s history.  Bouncing around the ring on the balls of his feet, he married relentless and blinding speed with an unerring accuracy on his left jab.  Williams barely managed to land a punch in anger.

Ali floored his opponent three times towards the end of round 2, and only the bell’s intervention prolonged the fight into the first minute of the third, when Williams again crumpled to the canvas.  It was an amazing performance - seven minutes showcasing boxing as close to perfect as it is ever likely to get.

2. Joe Frazier, 14th-round technical knockout, Manila, 1975: Ali triumphed in the rubber match, the sheer brutality of which eclipsed the previous two awesome meetings.

Ali called it “the closest thing to death”  Frazier stormed forward and swamped Ali with hooks, absorbing tremendous punishment in the process.  Frazier’s trainer, Eddie Futch, pulled his man out at the end of the 14th round.  Ali, ahead on the cards, was on the verge of quitting as well.

3. George Foreman, eighth-round KO, Kinshasa, 1974: “The Rumble in the Jungle” had extraordinary circumstances that called for Ali’s most extraordinary tactics.  To the disbelief of all observers, Ali opted to play “rope-a-dope” with the fearsome Foreman, lolling back on the ropes and inviting punishment. Foreman punched himself out and Ali pounced, a left and right to Foreman’s head dropping the champion and winning back the title for Ali.

4. Sonny Liston, seventh-round KO, Miami, 1964: The brooding, menacing Liston was supposed to put the loudmouth from Louisville in his place.  Cassius Clay - as Ali was known at the time - was pronounced “scared to death” by a physician before the fight.

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All the experts tipped a walkover by Liston.  But Clay went out and toyed with him, making the baddest man on the planet look flat-footed, fat and old.  Liston retired on his stool at the end of the seventh, making Clay - who announced his conversion to Islam after the fight - the world heavyweight champion.

5. Ernie Terrell, 15-round decision, New York, 1967: Ali was furious with Terrell, the top contender who refused to refer to him by his new name in the build-up to the bout. He made the challenger pay by inflicting upon him a sustained and deliberately drawn-out 15-round beating.  “What’s my name?” Ali repeatedly sneered during a humiliation as remarkable as it was unedifying.

6. Earnie Shavers, 15-round decision, New York, 1977: Ali was coming to the end of his career, and Shavers, a ferocious puncher, looked perfectly placed to take his title. Ali was badly hurt in the second round but survived, and his experience and sheer courage enabled him to regroup and fashion a lead.

By the end of the 14th, Ali was exhausted.  From somewhere, he summoned three more excellent minutes and had Shavers shaking at the end.

7. Joe Frazier, loss by 15-round decision, New York, 1971: Ali came in for some shocking punishment as he traded vicious blows with Frazier round after round. Ali was dropped and badly hurt in the 11th but somehow clawed his way back to the brink of victory until Frazier decked him again in the final round to underline his superiority.  Nevertheless, Ali’s star did anything but burn out in defeat.

8. George Chuvalo, 15-round decision, Toronto, 1966: Chuvalo was a rough, tough brawler, virtually impossible to knock out, who fancied his chances of pulling off a momentous upset and claiming the world title.  But the Ali of 1966 was an unforgiving boxer, one on top of his game.  The champion let Chuvalo whack away to negligible effect, then smoothly did enough to take every round but one.

9. Joe Frazier, 12-round decision, New York, 1974: Bad blood simmered between the pair before their second meeting, culminating in a brawl in a TV studio.

In the ring,  Frazier - rebounding after losing his world title to George Foreman - pushed forward as usual, looking to land his devastating hooks.  Ali, still on the comeback trail after dodging the draft, tried to pick him off.  Ali rocked Frazier in round 2 and went on to gain revenge on points.

10. Leon Spinks, 12-round decision, New Orleans, 1978: Spinks had shocked Ali seven months earlier to claim the title.  For the rematch, Ali was in better shape, while the upstart champion was ravaged by personal problems.

Ali moved better the second time around and negated Spinks’ strengths to gain a clear win on points win and reclaim the title for the second time at the age of 36.