Cotto is no pushover for anyone. That being said, Hearns by knockout. I could see it happening in the early to mid rounds.
As many have said, this is a terrible match up for Cotto. Hearns is nightmare for just about anyone at 147, and Cotto's only hope would be to try to wade inside, catch Tommy, and take his legs away. That usually resulted in in Hearns' opponent waking up in the dressing room, and I see no reason why this fight would be any different. Hearns was an awesome WW.
Hearns by early KO. Cotto would be game as always but that's not enough with this kind of mismatch...:-(
I think Hearns has a legitimate chance of ending this argument within the first two rounds. Too the guy who says, "Cotto has a pretty good defense". ...No he doesn't.