That's why he has to drop the key individuals that are messing up. Let them learn off the pitch and see how someone else plays the from the sidelines so it's a learning experience.
On a side not, did you see that bullshit pass Ozil pulled off when one on one with the keeper and on his preferred foot to score? For all his footballing intelligence, why in the world would he cut the ball back to Ramsey who hadn't set his feet properly and and had a defender right in front of him that could have potentially blocked the shot if Ramsey tried to shoot? We were lucky Ramsey improvised with the flick and Aubameyang wasn't called off side. Emery has to speak Ozil about that sort of shit.