Jim Irsay can now also boast Muhammad Ali's WBC championship belt which 'The Greatest' won against George Foreman in the 'Rumble in the Jungle' in addition to NFL franchise the Indianapolis Colts.
Bidding on the item until nearly 4AM on Sunday morning, Ali superfan Irsay paid $6 million for the item which is considered one of the most treasured in boxing memorabilia.
Heritage Auctions say that the belt is one out of just two known WBC belts linked to Ali, with the other unlikely to be sold as it is kept in a private museum collection.
Irsay, whose father Robert made his fortune in the heating and air-conditioning industry and bought the Colts when his son was 12, can also lay claim to the shoes Ali wore in the 'Thrilla in Manilla' in 1975 against Joe Frazier and also his walkout robe from a 1965 rematch with Sonny Liston that was his first appearance since ditching Cassius Clay and changing his name.
Irsay is a collector of memorabilia in general and has purchased documents written by the US founding fathers and rock and roll items such as Pink Floyd guitarist Dave Gilmour's black Fender Stratocaster which went for $4 million.
Ali's WBC belt is among the most expensive auction items Irsay has bought but it was not awarded to the fighter when he beat Foreman in 1974 and instead two years later when belts started being distributed.
Ali defended the WBC crown an impressive nine times before Leon Spinks dethroned him in 1978, and then retired in 1981 with a 56-5 record.
Aged 74, Ali passed away in 2016 amid declining health and had been battling Parkinson's Disease since the mid-1980s.