Amid growth in the sports memorabilia market, Sotheby’s is introducing a Sports Week series.

Muhammad Ali and Joe Frazier during their world championship bout in Manila in September of 1975. Nik Wheeler/Corbis via Getty Images
On October 1, 1975, heavyweight boxers Muhammad Ali and Joe Frazier met in Quezon City, Philippines, for a match that would go down as one of the greatest in boxing history. Nicknamed the “Thrilla in Manila,” it marked the third and final bout between the bitter rivals.

The satin trunks worn by Ali, who went on to win the brutal matchup, are now expected to realize between $4 million and $6 million at auction. They will headline Sotheby’s Sports Week, an inaugural sale series with more than 350 sports collectibles ranging from iconic milestones in sports history to items fresh off the court.

The auctioneer’s new initiative will take advantage of a burgeoning market for sports memorabilia that is expected to reach $227 billion by 2032, according to consulting group Market Decipher. “The market for unique sports artifacts has been enjoying unprecedented growth as collectors continue to chase the best-of-the-best objects, with a particular desire to acquire those that are ‘fresh to market,’” said Brahm Wachter, Sotheby’s head of modern collectibles, in a statement.

Sotheby’s has hosted several major sports sales in recent months, including the $7.8 million sale of Lionel Messi’s game-worn 2022 World Cup final jerseys in December and its February auction of Michael Jordan’s $8 million sneaker collection. In November of last year, it entered a multi-year partnership with the NBA to offer game-worn items at auction.