In order to defeat Mayweather or even have the opportunity to come close to it; you have to have a high outpout and push him to fight a fight that takes him out of his zone. Example is the Castillo Fight and also the Cotto fight. Yes, Cotto did loose but I had him winning 4 to 5 rounds which is a lot compared to other opponenents. Canelo fights in spurts; he cannot do this against Mayweather and sadly; this will be his downfall if they fight, or if Canelo fights someone who will throw push the action. Did you notice how many times; Canelo would take breathers in the fight? It's not the first fight where he does this same thing. He did it against Shane Mosley and others as well. The kid is young though; and for his age; he is doing amazing; however at this point Mayweather defeats him via UD. :bbb
Well, we still haven't seen Mayweather/Guerrero. After that fight, I think everyone would have a better gauge as to how the fight might fare.