He played his ass off in that atletico game. He showed really good grinta and stamina in that game as a winger. If he can consistently apply that type of Game as a midfielder, he would be good to go.
What worries me is his decition making, he seem to have zero confidence in him and whatever he does goes to shit.
What i want of him is to see first and foremost, sacrifice and he is very good as that because he always gives his all. After that, i would like him to try more his passing game, and last but not least, i want him to return to his first season shooting form, when every ball he kicked had a purpouse. Now he is always in tight positions and gets hasty as fuck to kick the ball into the stands.
Maybe as a midfielder he will have more time to aim his shots instead of being always rushed with the defenders in his face when he plays as forward.