He'd known that he was leaving himself open to attack by grabbing her hand like that, and he's prepared for it - but only enough for him to shift a little to take the punch on the side of his cheek instead of in the eye or to the nose.

Sam hisses in pain, but doesn't let that slow him down. He ducks down, ramming his shoulder into her diaphragm - hoping both to knock the wind out of her and to be able to pick her up and keep her tossed over his shoulder as he straightens.