Weight Drained??

Have there been any fighters that were KO/TKO'ed at a particular weight (middleweight or above), blamed it on being weight drained and moved up to become undisputed world champion at a higher weight?

I bring this up as David Haye moves up to heavyweight. David was TKO'd and has tasted the canvas more than once at cruiser (which he seems to blame on making weight). I understand at Cruiser he was successful after getting sparked, but I wanted to see what the history is, especially at middle weight and above, for a fighter with such a history that has turned things around and dominated a higher weight class.

He never got Ko'd at 140 but Cotto looked stronger at 147 and seems to have a stronger chin at that weight.
He got rocked a few times at 140.