MLB Network did some digging and found out the issue/history.
Back in 2010 Gomez homered off Maholm...next AB Maholm his Gomez. Three months later Gomez is swinging to kill, smokes a double off of Maholm....next time up Maholm his Gomez near his knee.
Fast forward to today and Gomez was ready immediately and gave him the insane crazy look after he missed then just murders the next pitch, takes 9 seconds to get to first and yaps all the way around...and points to his knee while glaring at Maholm.