Mosley beats Mayweather if Mayweather comes in undertrained and rusty. I don't see Mayweather ever coming into a fight like that. Mayweather always trains like a fiend and he's too much of a natural boxer to ever be extremely rusty. Plus, he still workouts.

In terms of styles, I think Mosley has a hard matchup with Floyd. Mosley has basically fought the same type of fighter for too long IMO. Collazo is a little slick but he's not elite and broke his thumb in the second round of that fight. Margarito, Mayorga, Vargas, and Cotto would all put pressure on Mosley which allowed Mosley to have a stationery target to land combinations and use his handspeed. Cotto has boxing skills that Tony, Mayorga, and Vargas (at that point in his career) didn't have. Cotto was able to box effectively on the move at times with Shane and that's what got him the decision. Mayweather won't be the aggressor in the fight so Shane won't have a stationery target to land combinations on. Plus, at this point the only speed Mosley has is handspeed. He's more stationary on his feet than ever, he's slow with his upper body movements, and quite honestly, his defense his always been a bit lacking. Cotto's jab gave Mosley fits and Mayweather has one of the best jabs in the game when he uses it. Mayweather's upper body speed and footwork is the best in the game behind only maybe JoeCal. I see Mosley pressuring Mayweather all fight but Mayweather's footwork and jab confusing and frustrating Mosley all night and not allowing him to get off. I also see Floyd landing a ton of clean and crisp right hand leads all night. It's a UD for Floyd with scores around 116-112 or 117-111 IMO.