The gloves worn by Muhammad Ali in his legendary first bout against "Smokin" Joe Fraizer in 1971 are expected to reach in excess of $500,000 at Heritage Auctions on July 31.
Referred to as The Fight of the Century, the bout took place in New York's Madison Square Garden with support for each fighter split down ideological lines - supporters of Ali (due to his refusal to fight in Vietnam) were left wing and anti-war, while Frazier's supporters were (by default) conservative and pro-war.
Both men were undefeated, with each claiming the title of world heavyweight champion - with the result that the pre-fight hype was at fever pitch when they took to the ring on March 8.
The bout lasted the full 15 rounds, the advantage swinging as each man gained and lost - up until the 11th, when Frazier began to pull ahead.
Despite taking a savage left hook early in the final round Ali stayed on his feet until the end. The judges decision was unanimous - Frazier was the victor.
The gloves are sold alongside a letter of provenance from Ali's trainer Angelo Dundee, who wrote: "The Ali-Frazier gloves have been in my family's possession from the time I cut them off Ali's hands.
"My wife and son brought them home from New York the day after the fight. I labelled the gloves inside the laces."
Last year a pair of gloves worn by Ali in his 1964 bout against Sonny Liston sold for $836,500, while UFC fighter Lorenzo Fertitta reportedly paid $1.1m for a pair used against Floyd Patterson in 1965.
You can check out all our available sports memorabilia here.
Follow the link to our free newsletter for the latest from the world of collecting.