Yeah, it's a lot better to judge him over 20 minutes in a pre-season game.
I must say that I'm impressed that he's managed to play 20minutes of football, but I'm blown away that he's done it in a single match. We've turned a corner and we may get over 60 minutes of football from him this season.
Disclaimer: I'm in no way suggesting he may play 60minutes in a single match. I'm not mental.