I think Sanchez and Aurier, for different reasons, are part of the "almost good first team players" category. First of all, in my opinion they are both underrated. Sanchez is very good at actually defending - that quality is more often recognized than Aurier´s good ones. But they are both - and that´s not an unfair criticism - ready to coast us a goal every game, no matter how well they are playing.
Against City, Aurier made the penalty. In my opinion, that was not a penalty - or at least not something V.A.R should be interfering -, but it was a mistake anyway. And Sanchez gave away a bad pass, in the early minutes, that could have also coast us the game if they were sharper. Not for the first time.
But I like both.