For me, De Gea really showed his immaturity today. No doubting his shot stopping ability, and if it wasn't for him then I'm sure we would have lost. But every time he caught the ball, he was looking for an outlet immediately. He seemed to be trying to urge us on and go and grab a second, but the rest of the team's mentality was to sit deep and defend what we had. There was a point where Rio tapped him on the shoulder, visibly said "slow down" and De Gea essentially ignored him and tried to find Valencia. It's an experience thing, and I'm sure he'll learn from it.
This is not a slating of him, just something that will come with age and experience.