The trunks Muhammad Ali wore in his 1974 Rumble in the Jungle fight against George Foreman will sell at Grey Flannel Auctions.
They're offered with an opening bid of $30,250.
Ali's 1974 bout against Foreman in Zaire was one of the biggest fights of all time
The fight was held in Zaire (now the Democratic Republic of Congo), which was then under the control of dictator Mobutu Sese Seko.
It ended in a spectacular victory for Ali, who knocked out Foreman (then the undefeated world heavyweight champion) in the eighth round.
Ali spent a couple years in the wilderness after he was beaten by Joe Frazier in 1971.
The Rumble in the Jungle bout marked a return to form, showcasing his technical mastery.
He utilised his now famous "rope-a-dope" technique to tire out the much more physically powerful Foreman, before delivering the finishing blow.
The trunks were last sold at auction for $57,500 in 1997, a figure they look likely to exceed by a considerable margin when the auction ends on May 25.
The inner label reads: "EVERLAST - MADE IN U.S.A. - Made Expressly For MUHAMMAD ALI".
Ali's gloves from his 1965 "Phantom Punch" bout against Sonny Liston realised a boxing memorabilia record $965,000 in a 2015 sale at Heritage Auctions.
We have a striking Muhammad Ali-signed artwork for sale.
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