WATCHING an old black and white film of a young Cassius Clay entering the ring at Wembley Stadium on June 18 1963 to face Henry Cooper in front of 55,000 fans is like watching footage of the first moon landing, it’s that special.

There was a joy and innocence about Clay back then. It was the year before he schooled the fearsome Sonny Liston over eight legendary rounds in Miami to claim the heavyweight title at just 22, before defiantly announcing his rebirth as Muhammad Ali, follower of Elijah Muhammad, leader of the Nation of Islam.

By the time he climbed through the ropes to face Cooper — sporting a red satin gown with the words “Cassius Clay the Greatest” emblazoned across the back, and with a crown perched on top of his head — Clay had been fighting as a professional for three years. And in that time he’d already made waves with his uncommon bombast and a style of fighting that seemed to straddle the line between ballet and performance art.

In a wild departure from your stereotypical heavyweight, Clay flitted across the ring like a stone skimming water, throwing punches from angles that defied the laws of physics, offending in the process purists of pugilism everywhere for whom a flat nose and cauliflower ears were the non-negotiable requirements of respect in the squared circle.

In the case of Cassius Clay, boxing really was the sweet science, under whose strictures getting hit was tantamount to a high crime. For a young man who’d just embarked on a mission to reinvent the character of heavyweight boxing, bamboozling rather than bludgeoning opponents was the primary objective, which he achieved with effortless grace — fight after fight.

Already famous as Cassius Clay and destined for greatness as Muhammad Ali, he arrived in London for his first professional bout overseas to huge fanfare and armed with his by now trademark poem: “It ain’t no jive. Henry Cooper will go in five.”

Cooper at 29 had held the British and Empire heavyweight title for five years. His last defence before facing Clay had seen him prevail less than impressively on points against local rival Brian London. This, combined with the fact that he’d been knocked out by Zora Folley in London in 1961, meant that Clay was justified in looking upon his foray across the pond as just another day at the office.

How wrong he was.

John Cottrell in his classic account of the fight “Clay v Cooper, The Louisville Lip Tastes Henry’s Hammer,” reveals that Clay was so confident about the outcome of the fight that he broke off training in Miami a full month before. “I’m tired of training to fight stiffs,” Clay grumbled. “All I want is a crack at Liston.”

Clay arrived in London two weeks prior and swanned around the city like a tourist rather than a man preparing for a fight. He posed for pictures outside Buckingham Palace, visited a top men’s outfitter and emerged with a bowler hat and cocktail jacket, went nightclubbing and even took time to visit the dog races. Everywhere he went he was mobbed by Londoners desperate to see The Louisville Lip up close and bag themselves an autograph.

In between his busy social calendar, Clay did manage to fit in some training. Early morning roadwork was undertaken in the company of his younger brother Rudy and sparring partner Jimmy Ellis; the three of them running down Regent Street, along the Mall and through Hyde Park. Meanwhile, when it came to his training base, he opted for a specially adapted Territorial Army drill hall opposite White City underground station.

As for the fight itself, a packed and smoke-filled Wembley Stadium witnessed Cooper come out in the first round on a seek and destroy mission. Giving away an astonishing 22lbs in weight to his considerably younger and fresher opponent, who himself had weighed in at nimble 207lbs, you would not have known it from the way the Englishman forced Clay back against the ropes, peppering him with shots to the body, arms, shoulders and any other part of Clay’s anatomy that was available to be hit.

In the second round, fresh from being on the receiving end of a bollocking from Angelo Dundee in his corner, Clay began to establish the jab and, with it, his dominance.

Cooper was renowned for being prone to cut easily, and soon enough Clay opened him up above the left eye. Having predicted a fifth round stoppage, Clay proceeded to toy with Cooper in the third round, holding his hands low and showboating as Cooper, vision blurred with blood from the cut above his eye, tried to get past his opponent’s fast and accurate jab to land something, anything, to try to turn things round.

It was towards the end of the fourth round that a golden moment of boxing history was made. Cooper unleashed his trademark left hook, “Enry’s Hammer,” which connected flush to send Clay crashing down to the canvas against the ropes. 

Remarkably, the 21-year old was back on his feet within seconds, a feat in itself given the thunderous impact of the punch that had just put him down. Moments later the bell went, whereupon Angelo Dundee guided his fighter back to his corner on unsteady legs.

Here one legendary moment was followed by another, when it was claimed — though as it turned out apocryphally — that Dundee made a small tear in one of Clay’s gloves worse in order to buy his fighter more time to recover while replacements were found and brought to the ring. Though, yes, there was a slight tear in one of Clay’s gloves, Dundee did not make it worse. The glove in question did not come off either. Instead, the tear was patched and Clay was able to fight on, with the time taken between rounds only six seconds over the regulation minute.

Precisely as Clay had predicted going into the fight, the fifth round would be Cooper’s last. With blood now streaming down the proud Englishman’s face and over his eyes to leave him blind he could not conceivably continue, leaving the referee no choice other than to step in and end the fight.

In the aftermath Clay, who when he met Cooper in the ring once again three years later in 1966 as Muhammad Ali did so as the most controversial figure in the US, began to develop an affection for the English champion that would morph into a friendship that endured. He also embraced the UK, where, like Paul Robeson before him, he never failed to find sanctuary from the hatred and animosity that stalked him at home.

Cooper fought on until 1971, when he retired after losing on points to Joe Bugner in defence of his British and Empire heavyweight titles. When Henry Cooper died in 2011, Ali issued a statement in which he said: “I will miss my ole friend. He was a great fighter and a gentleman.”