Knockout bids: These Muhammad Ali artifacts sold for top dollar at sports auction

The championship belt Muhammad Ali reclaimed when he knocked out George Foreman in 1974's "Rumble in the Jungle" fight sold at auction over the weekend for the heavyweight price of $6.18 million.

Indianapolis Colts owner Jim Irsay emerged victorious from what was described as a back-and-forth bidding war "worthy of the Rumble itself" by Chris Ivy of Texas-based Heritage Auctions. The belt was the highest-selling Ali artifact from a collection of more than 1,600 items amassed over the course of three decades by Troy Kinunen of Milwaukee, Wisconsin.

"Quite simply, it is the most comprehensive Muhammad Ali collection ever to come to auction," Ivy said in an earlier statement. "What Troy has done here is tell Ali’s life story with treasures that were present for every bout and every brag and every historic highlight in between. It’s one of the most extraordinary collections we have ever been honored to offer."

In a tweet Sunday afternoon, Irsay said he had added the belt to his collection of rock music, American history and pop culture artifacts, which is currently touring the United States. The belt will be displayed during shows Aug. 2 at Chicago's Navy Pier and Sept. 9 in Indianapolis.

“Proud to be the steward!” Irsay wrote.

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Ali's championship belt from the "Rumble in the Jungle" was the only item in Kinunen's collection to sell for $1 million or more during Heritage's July 21-23 Summer Sports Catalog Auction. The mouth guard through which the Louisville native shouted taunts at Foreman during the eight-round fight in the African nation of Zaire sold for $18,600.

Here's a look at some of the other top-selling Ali artifacts from the summer auction:

Muhammad Ali's robe from 'The Fight of the Century' vs. Joe Frazier

Selling price: $348,000

This red robe from "The Fight of the Century" was quickly removed from Ali's rotation after he suffered the first loss of his professional career to Joe Frazier at Madison Square Garden in 1971. Kinunen said he acquired the garment, which is autographed by Ali, when a storage locker belonging to the boxer's loyal cornerman, Drew "Bundini" Brown, went up for auction.

"Muhammad Ali had 61 professional fights … and there's not a robe for every fight," Kinunen told the Courier Journal. So the opportunity to get something that was worn by him in the ring for one of his fights is really, really miniscule."

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Muhammad Ali's robe from 1977 fight vs. Earnie Shavers

Selling price: $87,000

Another robe from an Ali fight at Madison Square Garden was among the top three most expensive items from Kinunen's to sell at auction. This autographed garment is a return to Ali's trademark black-and-white prefight attire — and the winner's circle. Ali defeated Earnie Shavers in 15 rounds to successfully defend the world heavyweight title for the final time of his career.

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Muhammad Ali's boxing gloves from 1976 fight vs. Ken Norton

Selling price: $63,000

Worn by Ali during his third and final bout against Ken Norton in front of a rowdy crowd at Yankee Stadium in The Bronx, New York, these autographed boxing gloves were the most expensive pair from Kinunen's collection to sell at auction. Ali won the fight in a unanimous decision to defend his world heavyweight title and improve to 2-1 against Norton for his career.

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Muhammad Ali and Henry Cooper's boxing gloves from 1966 fight

Selling price: $55,200

A package deal that crossed the $50,000 mark at auction, these gloves were worn by Ali and England's Henry Cooper for their bloody 1966 bout at London's Arsenal Stadium. Ali bested Cooper, a European heavyweight champion, for a second time by technical knockout; the fight was stopped in the sixth round due to a cut over Cooper's eye.

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Muhammad Ali's trunks from 1976 fight vs. Jean-Pierre Coopman

Selling price: $42,000

In his first fight since winning "The Thrilla in Manila," Ali wore these trunks when he knocked out Jean Pierre Coopman in the fifth round at San Juan's Roberto Clemente Coliseum. The trunks are signed by Ali and his assistant equipment manager Wali Muhammad, to whom the boxing legend gave many keepsakes from his career.

Reach recruiting and trending sports reporter Brooks Holton at bholton@gannett.com and follow him on Twitter at @brooksHolton.

This article originally appeared on Louisville Courier Journal: Muhammad Ali's 'Rumble in the Jungle' belt sold to Colts' Jim Irsay