Not sure what's happened to him. At Southampton, just 3 years ago he was technically gifted, confident on the ball, consistent and always popping up with great assists. Not sure if his confidence/morale is still at rock bottom after Jose froze him out of the Man Utd team. Or, if that spell at Southampton was just a one-off. He looks a totally different player.
Having said that, there's a player in there somewhere, you don't get big money moves to United if you're not at a good level. Think he needs dropping as he was shocking today. Maybe perservere a bit more, but if there's no improvement you might have to take a big loss on him.
What annoyed me (even as a neutral) was him bottling that tackle.