is one piece episode 598 filler?

Law is seen writhing in pain in front of the mysterious man named Vergo who revealed he was sent along with Monet to watch over Caesar. Before Law could muster some strength to retaliate, Vergo squeezes his heart which he has in his hand and proceeds to knock out Law with a Haki imbued Bamboo stick.

At the entrance of the lab, the G-5 marines are shocked at the scene before them, finding it hard to believe that Smoker was defeated twice in a day. The crews are wondering what attack did Caesar used to defeat their officers and the three Straw Hats as well.