"The public will go crazy for that fight," Arum told boxingscene.com. "Imagine Manny against either of these animals. ... Manny will have to become an 'animal' himself. Absolutely. These guys will make him an animal."
Before any of that can happen, though, Pacquiao will have to get past Juan Manuel Marquez on Dec. 8.
Rios and Alvarado are to fight this Saturday at the Home Depot Center in Carson.
The fight is expected to be a complete slugfest, with little dancing around and a lot of punching. And with a potential multimillion-dollar payday and Pacquiao on the horizon for the winner, there will be plenty to fight for.