Also, keep in mind that Pacquiao had his legs buckled by a Marquez left hook in Round 2 of their rematch. Luckily for Pac, it happened with about :02 left in the round and Marquez wasn't able to jump on him.
Marquez spent most of his career as a featherweight... if his left hook can wobble Pacquiao, it would stand to reason that a left hook from Oscar can have a serious impact on Pacquiao.
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