IF this is a serious fight, and not staged, Mayweather will play with him as long as he wants it to go on and end it certain and sudden. the skill set with his fists AND his abilty to defend and slip punches is so far superior to any MMA fighter.
What if they had MMA rules? I'm not sure. Mayweaher would have serious problems if he was put on the canvas, yet his hands and are so fast and skilled he could end it at the opening bell.
I doubt it. A pure hands striker has little chance against a top mma guy. To get close enough to punch puts him in the range of leg kicks, and a real ground and pounder would stay covered up, close, and take him down. On the ground it's all over. His face is cut up from elbows dropping in, he loses the use of a limb or joint, or he sees the lights dim as the O2 runs out in his brain.
