JMM by TKO. JMM is a Master boxer, and Campbell isnt powerful (meaning that he doesnt have one punch power) enough to impose himself over Marquez. So it would really be a boxing match which Marquez would obviously win.
I really think JMM will start breaking Campbell appart slowly with his supirior technical skill. Campbell will try his dirty tactics and but JMM will just punish him and finish the fight in the championship rounds.
JMM is the consummate professional, I don't think Campbell catches him slipping. Against Casamayor - a fight I thought Campbell won- he caught Casa sleeping. Casa was surprised the short notice opponent made him work and he got outworked. Against Diaz - a fight I picked Campbell to win even before it was announced- he exploited Diaz' inexperience. Against JMM he can exploit neither. JMM is moving up in weight, coming off a loss and knows he is fighting the linear champ. No way JMM is caught sleeping. Campbell can't really try to take JMM to the deep end without drowning himself, either. If he goes the insane workrate route he used against Diaz, he gets countered all night - or as long as it lasts. If he plans to box, he better bring a lunch and a signed permission slip because he's getting schooled. JMM, UD.