Muhammad Ali’s final knockout victory came against British scaffolder Richard Dunn using special punch that he learned from Bruce Lee

Muhammad Ali's last ever knockout victory came against gutsy Bradford scaffolder Richard Dunn, who left the ring with no regrets.
At the time of the fight in 1976, The Greatest was 34 years of age and well into his second reign as world heavyweight champion.
Two years prior, in 1974, Ali beat George Foreman to reclaim the crown in the 'Rumble in the Jungle' and went on to emerge victorious from his 'Thrilla in Manila' trilogy fight with Joe Frazier in 1975.
The first half of the following year saw the champion make three defences in four months against lesser challengers.
The third of these was set to be against the European champion in Munich.
Germany's Bernd August was lined up for the title shot and had to get through one last fight with the British and Commonwealth champion in order to secure his spot as Ali's next contender.
The Brit, Dunn, was not even able to fully dedicate himself to boxing, remaining in his job as a scaffolder during his career and being unable to afford to pay for sparring partners.
He was thought to be a very winnable fight for August as he'd already had nine losses in his career, while the German had been beaten just twice previously.
However, Dunn had other ideas and produced the performance of his life, stopping August in three rounds to claim the European title and take his spot to fight Ali.
Therefore, on May 24, 1976, it was he who travelled to Munich to fight The Greatest, becoming an overnight celebrity when the bout was confirmed.
Dunn instantly made himself a local household name and was even surprised by an episode of This Is Your Life in the build-up.
Ali featured in the programme and took the opportunity to respond to the suggestion that Dunn's southpaw stance could trouble him.
The famously fantastic talker replied: "I don’t care if it is the northpaw, southpaw, eastpaw or westpaw, it ain't going to matter what paw you are when I get you."
In the fight itself, Ali was proved right.
Dunn gave a solid account, trying everything he could to trouble the champion and leaving the ring knowing he'd done his best.
Ultimately, though, he was significantly outgunned and found himself floored five times.
The final knockdown came in the fifth round, as Dunn was smashed by a super-fast short right hand which Ali later revealed he'd learned from taekwondo grandmaster Jhoon Rhee.
Rhee described it as the 'AccuPunch' and explained that he'd been taught it by the legendary Bruce Lee, which was what piqued Ali's interest.
The idea was for the 'AccuPunch' to be a remarkably fast shot based on human reaction time, which should be executed so quickly that it had already landed before the opponent's brain could respond to block it.
While not divulging the full secrets of the technique, Ali said: “It acts at the exact moment you decide to hit, and there is no lag time at all.
"It is instantaneous. It moves at tremendous speed with no warning and accelerates like a bullet in flight. You can hardly see it."
After being hit by the incredibly fast right hand, Dunn rose to his feet on unsteady legs and referee Herbert Tomser mercifully waved off the contest while Ali showboated by rapidly windmilling his right arm to thrill the German crowd.
There was no shame in defeat for Dunn - in fact, the reaction was quite the opposite.
When he returned home to Bradford after being KOd, he was given a parade as if he'd won, with thousands turning out to congratulate him while he was driven around in a convertible.
"It was the biggest surprise in my life," Dunn later said of the hero's welcome, "I didn't know what to do, I didn't know what to say. I was dumbfounded."
For Ali, this would turn out to be the final knockout win of his historic career.
He once again showed off his famous ability to predict what round he would finish his fights in. Written inside one of his gloves were the words, ‘Ali wins,’ while the other had, 'Round five’.
The Greatest won three more defences on points before losing and regaining the title in two fights with Leon Spinks.
When Ali returned after that, he was beaten comprehensively by Larry Holmes and Trevor Berbick, forcing him into retirement.
The KO of Dunn, with the aid of Bruce Lee, was Ali's final finishing punch.