The result leaves Haye's boxing career in the balance, after the 34-year-old's body seemed to physically break down in front of the London crowd after suffering an apparent achilles injury in the sixth round.
But the Hayemaker took the fight into the eleventh round - having not been beyond five rounds since 2011 - but it was Bellew, tiring himself having stepped up from cruiserweight, who eventually found the strength to finish the fight.
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FIGHT UNDERCARD RESULTS
Sam Eggington defeated Paulie Malignaggi via KO08
Ohara Davies defeated Derry Mathews via TKO3
Katie Taylor defeated Monica Gentili via TK05
Dave Allen defeated David Howe via KO2
Lee Selby defeated Andoni Gago via TKO9