JMM is one of my favorite fighter and im not too fond of Mayweather, but PBF would beat him in a near mismatch, and stop him before the 8th imo. Floyd is too big and strong. Marquez has done very well at lightweight, but hes been hurt by men much smaller than Mayweather. JMM is not even a big lightweight and fighting above that weight, he will be at a huge disadvantage imo. I truly believe that Marquez is a better fighter than Floyd, but he would be up against too much. It would really tell a lot about Floyd if he comes back to fight him instead of taking on a bigger challenge. Then again, nothing we didnt already know.