Ali's bout with wrestler 'incredible stupid'
Floyd Mayweather's big-money bout with Conor McGregor is not the first time a top boxer has put his reputation on the line against a martial artist.
Muhammad Ali agreed to travel to Japan to take on wrestler Antonio Inoki in a so-called 'mixed martial arts championship of the world' in June 1976.
The initial plan was for the pair to follow a script in which Ali would pummel his opponent, who would then claim an improbable victory while Ali was distracted.
But the event, which was beamed back to 150 closed-circuit cinemas in the US, did not go to plan.
A plainly terrified Inoki spent most of the bout lying on the floor trying to kick Ali's legs, and after 15 rounds the laborious spectacle was declared a draw.
Ali might have emerged from the bout USD 6million better off but he also subsequently suffered infections and blood clots from the attacks on his legs.
In Ali's official biography, 'His Life and Times', written by Thomas Hauser, promoter Bob Arum recalled: "It was the nightmare to end all nightmares."
And Ali's long-term physician Ferdie Pacheco offered an opinion on the contest which retired former world champion Mayweather - who has agreed a deal to fight mixed martial artist McGregor in a boxing match in August - would perhaps do well to heed.
"Fighting Inoki was an incredibly stupid act," Pacheco told Hauser.
"To subject a great legendary fighter to a carnival atmosphere like that was wrong.
"Ali was a showman, but this wasn't much of a show, and it put his entire career in jeopardy for some dollars that he could have made just as easily without risking his reputation and his health."
That was not the only boxer versus wrestler match on the card. Earlier, former Ali foe Chuck Wepner - the inspiration for the Rocky movies - was thrown out of the ring in the third round of his bout against 7ft 1ins Andre The Giant.