The jock dates back to Ali-Frazier I in 1971 … known as, “The Fight of the Century,” one of America’s most historic sporting events. Frazier — who, like Ali, was undefeated — won by unanimous decision.
Frazier gave the jock to his buddy the night of the fight … who held onto it for almost 40 years before selling it to a memorabilia dealer in 2009.
The collector hooked up with Goldin Auctions … who will now be auctioning off the super rare item starting July 11th. Starting bid is $5K.