Amir Khan has denied Terence Crawford’s accusations he “quit” six rounds into their WBO welterweight title fight at New York’s Madison Square Garden.

The 32-year-old had already suffered a knockdown in the opening round and had continued to take significant punishment up to the sixth when Crawford landed a sickening low blow.

Khan was by then also appearing to struggle with an injury to his right arm and, instead of taking the full five minutes he would have been allowed to recover, was withdrawn by his trainer Virgil Hunter having used only a fraction of it, ensuring his defeat via stoppage.

The conclusion was both unsatisfactory and out of character within the context of Khan’s career, in which of his five defeats four have come inside the distance but previously without questions surrounding his heart.

Saul ‘Canelo’ Alvarez’s knockout of him was devastating and against both Breidis Prescott and Danny Garcia he was admirably attempting to fight on, but the crowd in New York was so angry at his withdrawal against Crawford that he was loudly booed until he left the ring.

Crawford, 31 and after Ukraine’s Vasyl Lomachenko widely considered the finest fighter in the world, even interrupted Khan’s post-fight press conference to insist he “tell the truth” about his defeat, but his challenger responded: “I could feel it in my stomach.