American businessman Jim Irsay bought boxing legend Mohamed Ali's championship belt for $6.18 million, which the latter acquired in 1974 after facing George Foreman in the legendary fight called "Rumble in the Jungle”.

The Indianapolis Colts owner announced the purchase Sunday in a Twitter post, saying he was "proud to be the custodian" of the historic World Boxing Council belt.

Irsay hinted that the object could be presented at an exhibition of his collection in August in Chicago, and in September in Indianapolis.

The businessman is used to spectacular purchases. He notably owns guitars belonging to Elvis Presley, John Lennon, Prince... as well as the original manuscript of the Alcoholics Anonymous guide written by Bill Wilson in 1939.

The sale price for the belt, set early Sunday by Heritage Auctions, reported by Sports Collectors Daily, has been called one of the highest prices ever paid for a sports collectible.

Ali defeated the previously undefeated Foreman in Kinshasa, Zaire (now Democratic Republic of the Congo) by knockout. in the eighth round, to reclaim the world heavyweight crown.

Ali, who died in 2016 aged 74, retained the WBC crown until losing to Leon Spinks in 1978.