In a 1952 light heavyweight title challenge Sugar Ray Robinson collapsed from heat exhaustion at the end of round 13 and retired on his stool.

Ali and Frazier were pretty close to collapse at the end of the Thrilla in Manila.

Mike Weaver after his 15th round KO of Big John Tate.

Wladimir Klitscko was hurt in the fight against Lamon Brewster but it was his poor conditioning that let him down in the end.