Muhammed Ali Thrilla in Manila boxing shorts up for auction expecting to fetch £4.75 million

The Thrilla in Manila - the legendary fight between Muhammed Ali and Joe Frazier - sits in the boxing history books as one of the greatest bouts ever and now fans can buy a piece of the action, if they have around $6 million. In 1975, 'Smokin' Joe' and Ali - two of the best heavyweights ever seen - took to the ring in Africa for a title match in what the self-proclaimed 'greatest' would later describe as the toughest match of his career.

Now, the signed shorts worn by Ali for the bout - which he said left him "the closest thing to dying" he had done - are going under the hammer, and could fetch up to £4.75 million ($6m). The Thrilla in Manila was the third time the pair met, with Frazier winning 'The Fight of the Century' in New York City at the start of the 15th and final round, before Ali triumphed in a rematch at Madison Square Garden in January 1974.

On October 1, 1975, in temperatures pushing 49C (120f), Ali cemented his reputation as 'The Greatest' with victory. A billion people worldwide tuned in to watch the fight, still regarded as the greatest and most brutal boxing match of all time 50 years on.

You might expect the trademark silk Everlast shorts - pure white save for the black belt line and thin black racing stripes down each leg - to have been bloodied during the brutal bout, but after 14 bruising rounds, they remained spotless. They will go under the hammer as part of Sotheby’s New York Sports Week of sales, which runs until April 10.

"It was like death," Ali said of the bout. "Closest thing to dying that I know of. We went to Manila as champions, Joe and me, and we came back as old men."

For his part, Frazier suffered damage to his eyesight in the fierce match, which never returned to normal. The 31-year-old fought just twice more before retiring.

Ali boxed for six more years, retaining, then losing, then recapturing heavyweight titles. He retired in 1981 and just three years later, was diagnosed with Parkinson’s. He died on June 3, 2016, at the age of 74, after three decades of battling the disease.

The sale will also feature Michel Jordan's Air Jordan 11s from Game 5 of the 1996 NBA Finals, valued up to £317,000 ($400,000). They form part of a collection of 50 sneakers worn by some of the NBA's greatest ever players.