I think last night showed one of the difficulties that Mourinho will have working with this team. If we'd won 1-0, you'd have said "okay it's not pretty but that was a Mourinho masterclass. Got a goal, soaked up pressure and allowed them few chances."
The problem is, Aurier was good but had a couple of pretty big brainfarts particularly the one that led to the non-pen (I don't think it was a foul). Sanchez was excellent but had a massive brainfart in the first half when he gifted Rashford a very good chance. Dier had a brainfart on the penalty and Winks was defensively careless and naive. Hugo and Davies were really, really good. Close to flawless defensively but we all know Hugo has mistakes in him.
Even when our defence is good, like last night, there are just too many big mistakes in them.