Come to think of it, a Mayweather VS Pacquiao fight is still possible, everyone is crediting Marquez's KO as ruining this dream megafight.
BUT
Let's not forget that it is unanimously agreed that Pacquaio was robbed against Bradley, his fight against Shane Mosley was a mismatch, he busted Margarito's eye up, and the Clottey fight again was another mismatch and a joke too.
Lets not forget that the man has been KO'ed twice prior to the Marquez fight, and has been beaten before, at times only to come back and whoop ass again.
So it's not like Pacquiao VS Mayweather will be an undefeated fighter vs an undefeated fighter, the story angle has changed. With the focus on Pacquiao to bounce back from a thundering KO from Marquez (who lets not forget, was behind on points and was actually doing well... I was behind Marquez on this fight too, so this ain't no bias post).
IT CAN still be done.