Marquez couldn't knock down Pacquiao in 3 previous fights. Not only KO's him but drops him like a log with the first haymaker he connected in the 4th fight, an overhand right he hit Pacquiao with several times before.
Mayweather could KO Pacquiao. Pacquiao better not get hit cleanly if he doesn't want to sleep on the canvass again.
You may be right, so far Pac has been legit tested two times and Mayweather's team indicated that he had been tested as well but nothing has been confirmed. I think dude is juicing and paid off the commission to skip out on the testing part. Money talks and that greaseball throws money around like it's nothing. Sad too, all Pac wants is a "fair fight".
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