Roberto Duran was mean and he could really cross the line with the way he acted, but he backed it up and I don't think Manny would really appreciate Roberto's charisma...I don't see any fighters out there today that are as menacing as Duran was and the odd fact is Roberto was an EXCELLENT pure boxer, great defense, solid chin, good handspeed, and I don't see Manny Pacquiao taking the beating Ray Leonard did and lasting the distance.

These would be interesting matchups for Pacquiao though:
Naseem Hamed....I would have LOVED to see Naz get starched!

but seriously

Willie Pep
Salvador Sanchez
Alexis Arguello
Aaron Pryor
Carmen Basillio
Kid Gavilan
Azumah Nelson
Pernell Whittaker
Sugar Ramos
Sandy Saddler