I think Floyd will give any fighter a hard time. While I don't care for him personally, as a boxer he has superb skills and fights "smart", using defense and counterpunching effectively, Undefeated for a reason.
I think Pacquio is the best fight out there for Floyd now, but not sure he could win. Regardless, as you said, it's the fight everyone wants to see, and I would be rooting for Manny to shut Big Mouth's yapper.
From everything I have read, I don't find any merit to the drug accusations against Manny...but only his dealer knows for sure.
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Thanks Dave, Julian, James, Kelly, Peter, Gerry, Dave, Mo, Frank, Týr and Mr. Mark!