An iconic piece of memorabilia from legendary boxer Muhammad Ali is up for auction and is expected to be sold for an eye-popping number.

Ali's renowned fight-worn Everlast boxing trunks from the "Thrilla in Manila" are being auctioned by Sotheby's with an estimated price of $4-6 million. The current high bid stands at $3.8 million, and the auction will close on April 12.

The "Thrilla in Manila" was the culmination of Ali's longstanding rivalry with Joe Frazier. Their first meeting in 1971 was dubbed the "Fight of the Century," with Frazier emerging victorious. In 1974, they met in the "Rumble in the Jungle," with Ali winning the second time around.

The following year, the stage was set for their trilogy fight with Ali's heavyweight championship on the line, and it featured one of the most memorable buildups in boxing history. Ali relentlessly threw verbal jabs at Frazier while promoting the matchup, causing an undeniable amount of animosity between the two.

When they finally met in the ring, Frazier's anger was apparent as he threw power punches early and often. However, Ali was able to withstand the barrage and go on the offensive. Frazier's corner threw in the towel after the 14th round, ending one of the best fights of all time.

Whoever lands the bid for Ali's famed trunks will be acquiring one of the most illustrious pieces of boxing history.