On 6 August 1966, Earls Court Arena in London staged Muhammad Ali’s fifth defence of the world heavyweight crown, and it ended in emphatic fashion. Before a crowd of 13,000, the 24-year-old champion dismantled Brian London inside three rounds, retaining the WBC, NYSAC and Ring Magazine titles with a clinical knockout at 1 minute 40 seconds of the third.

London’s path to the opportunity was unusual. Despite defeats to contenders such as Thad Spencer, he kept himself in the frame by overcoming Amos Johnson and benefitting from the persistence of his promoters Mickey Duff and Jack Solomons. Publicly, Ali was a 15-to-1 favourite, with bookmakers and experts alike seeing the Norwich-born challenger as a heavy underdog. The champion, already a global star, was guaranteed over $250,000 for the contest, while London pocketed less than half that figure. For the Englishman it was nevertheless a chance to seize immortality against a fighter already regarded as the finest of his era.

From the opening bell, the difference in class was evident. Ali, taller, faster, and lighter on his feet, circled the ring in perpetual motion, flicking jabs and combinations almost at will. London, 32 at the time, pursued doggedly, but his attacks were limited to single, hopeful swings. In the first round he did manage to land a solitary jab to Ali’s jaw, a rare moment of connection that briefly caught the champion’s attention. Yet the blow lacked the power to trouble Ali, and with no follow-up, the moment passed.

The second round continued in the same vein. Ali’s sharp right hand drew cheers from the crowd, while London struggled to close the distance. Although the challenger remained upright, his reluctance to let his hands go meant he was offering little more than a stationary target for the champion’s speed and reflexes.

It was the third that brought the inevitable conclusion. Spotting hesitation in London, Ali closed in, forcing him to the ropes. Then came a dazzling display – a rapid-fire flurry of punches, a dozen in the space of seconds, capped by a clean shot that sent London crashing to the canvas. Referee Harry Gibbs counted him out, and Ali retained his crown without breaking sweat.

For Ali, it was another demonstration of his brilliance – fast hands, showmanship, and the ability to finish when the chance arrived. For London, brave but outclassed, it was a night that underlined the gulf between a durable contender and an all-time great. History remembers it as one of Ali’s easiest title defences, but also as a reminder of just how untouchable he was in his prime.