mayweather will win for some dumb reason, as my friend said its gonna be funny ones gonna be looking for knock out and the other for a pin lol.
Actually show will be looking for a KO as well, for those that don't know Big show tried to pursue a career in boxing but because of his size nobody wanted to face him.
Its supposed to be a mix-martial arts exhibition match, so I assume they use the rules of their sport. For Mayweather, it means nothing like a groin shot, strike to the head, etc. and for Big Show it means no low-blows, no use of weapons, and so forth.