flippant title, but this sounds very serious. this isn't an excuse for losing, this is a reason. blimey. if he and Cain stay undefeated in their next fights and meet again, would be epic.

He took a severe beating in losing his heavyweight championship to Velasquez via a five-round decision. The morning after the bout, his urine was a very dark brown, the color of Guinness Stout beer.

He wasn't urinating blood, as some fighters do after a grueling match. Rather, the brown coloration of his urine was due to rhabdomyolysis. His muscle fiber was breaking down and getting into the blood steam.

It is a treatable condition, but it can be fatal under certain circumstances. There are numerous causes, but one is extreme physical exercise. Dos Santos trained so fiercely that he was pushing his body well beyond its natural limits.
http://sports.yahoo.com/news/mma--uf...181312353.html