Then Tszyu would have lost in his prime? Its funny how many people on here thought that Hatton would beat Floyd, know why? BECAUSE HE WAS A CREDIBLE OPPONENT. That wasn't cap locks I was emphasizing my point.

I think Quintana has effectively shown that Paul Williams is putz when fighting to a good mover, MAyweather would totally negate Paul's height just like he did to Ndou, Corrales by either fight on the outside beyond his reach, or fighting in close where Paul will not be able to get off anything effective.

Mosley doesn't have enough boxing skills, and never did to convince me he could ever have beaten MAyweather, IF MOsley was the type of guy who would come forward through anything and bang up PBF I would give Mosley a chance at lightweight in his prime, but I think he would respect Floyd's speed and power enough not to fight like a brawler, and Mayweather's movement would effectively nullify Mosley's offense, and his straighter punches would reach Mosley first just like Winky's did, just like FOrest's did, where they had height and reach Mayweather has the speed to match Mosley's.

So that leaves Cotto, this would be interesting. I do think Mayweather could get Cotto's attention with his sneaky punching power. Hatton was rocked by Collazo who doens't hit hard, but Cotto was rocked by a lightwelterweight in Corley who didn't hit hard or was in his prime at all. That being said Cotto is very similar to Castillo in how he fights, but with a better defense, more speed, and better boxing skills, BUT he can't walk through what Castillo walked through I firmly believe if he tried to take the punishment Castillo did he would go down. There is a reason Floyd was able to stun Oscar, keep a 14 pounds heavier Baldomir in check. So Cotto is the closest guy to beating Mayweather, but I still don't think he would. Mayweather has evolved since his Castillo fights and knows how to beat that style effectively.