What weaknesses of Pacquiao have been exposed during Marquez/Cotto fights?

[Spacey1991]

list them....

Struggles with counter punchers
Can get frustrated when the other fighter is moving and not trading (ala Cotto, when he was moving, Manny wasn't doing anything and seemed to be getting a little annoyed).

[DuttyAlacrity]

Like Larry mentioned:
he is open to counter punches
not only is he not as effective against fighters that move and box but I saw glimpses of frustration when Cotto kept moving
he does get a bit wild and reckless at times
his defense is his overwhelming offense, if he is not effective offensively he may be out of the game
he is very very open to the jab