Problem is that the OP says prime, and we cant measure how Pac would do against a prime beast since he is not accustomed to fighting them.
Mayorga, at his a best at 147, still wasn't all that great. He beat a 'spooked' Vernon Forrest, that's about it. Pac beats Mayorga at 147 pretty clearly, and badly. Stopping him wouldn't be out of the question either.
Yeah, ok, Pac KO's Mayorga in 3 rounds, Lol, derp/ Cotto clearly has a much better chin than Mayorga, herp, derp
I can see him dishing out a Margarito style beating and Mayorga being stopped on punishment. Mayorga doesn't have Margarito's chin.
Either Mayorga KOs Pac (hurts him with a lucky bomb that turns the fight in his favor) or Pac wins every round and cruises to an easy UD...the latter is most likely.
Pac by decision. Once Pac feels Mayorga's strength he will stick and duck under Mayorga's swings, and STAY AWAY. Pac gets knocked down in the fight though