I think mayweather wins by stoppage, maybe not on his back, but he wins tko, he hits hard, but not as hard as pacqiou, hes just much more precise, his punches are like lasers, where pacqous are like cannonballs that are coming from all over the place, i still think its mays hardest fight, but pacqiou catches to many clean punches coming in due to maywaethers great timing and reflexes, scary moments for floyd in the fight, but it turns one sided after 4 and ends in 8 or 10