This season is about winning and getting to the playoffs. Gunnar isn't helping the offense reach that goal. Today he struck out with the bases loaded, the last 2 pitches were 92 mph fastballs right down the middle. If he can't hit those pitches, something might need to be done to get him straightened out.
Maybe platoon him with Urias at 3B? Maybe bring up Westburg to take ABs against lefties?