Jim Irsay’s purse strings were loosened early Sunday morning, with the Indianapolis Colts owner acquiring a rare item for his formidable collection: the championship belt given to Muhammad Ali after 1974’s ‘Rumble in the Jungle.’ The winning bid of $6.18 million was placed around 4 a.m. on Sunday, according to ESPN, and marks one of the highest prices ever paid for a piece of sports memorabilia.

Ali was awarded the belt over George Foreman after eight brutal rounds ended in a knockout. It is one of just two known World Boxing Council belts given to Ali; the other resides in a private museum, where it is “unlikely to ever see the hobby auction’s block,” according to Heritage Auctions’ listing for the belt sold to Irsay. It isn’t the first Ali-related item to come into the NFL team owner’s hands. Already in his collection are the shoes Ali sported in his ‘Thrilla in Manila’ bout against Joe Frazier, and the 1965 walkout robe Ali sported in his first match after changing his name from Cassius Clay.