But the thing is Mayweather has much more experience fighting aggressive Pacquiao type of fighters than Pacquiao does fighting slick boxers who counter and have great defense... Pacquiao looked alittle confused and frustrated by the retreating mosley( probably because he didn't expect Mosley to do that) and it will be 10x that when he fights mayweather who is a master of defense/counter fighting and moves far better than Mosley.
I think Pacquiao might trouble Mayweather early like Judah and other southpaws have in the past, but then Floyd will gather his composure and get his timing down and start to win rounds. Pacquiao has little experience fighting really slick defensive guys like May and I think he will be overly frustrated.