He's done the hard part already - transitioned from athletic game to old man game. He might as well play another 5 years now, guy doesn't jump at all and is still one of the best PF's in the league.
Win or lose he would have returned. Add to it the gimmie he missed over shane battier... Probably a foul but he lost mad weight in the offseason. Hes not ready to retire
He said in the post game press conference when asked about retirement that he has to honor his contract and he will be back. He wasn't happy with the question.