Max is a head case right now. He just doesn't seem to be a very happy camper. I don't know if that's a reflection of his performance, or if that is what's causing his issues. It's like you expect some revelation about him personally, that would explain his issues.
Kepler hasn't mastered hitting the bottom half of the ball, like a lot of power hitter have. As a result he hits the top half or rolls over on the ;pitch, making him a prime candidate for hitting ground balls.