The first goal encapsulated the problems with United. Midfielders don't track their runners and don't communicate to pass players on when they're injured. The left hand side of the team doesn't track its runners, the right-hand side drops off and retreats to the comfort zone of their penalty box. Meanwhile, Maguire ends up caught in no-man's land, stuck between pro-actively stepping up to resolve a problem not of his own making, and stepping off in a way he's instinctively more accustomed to do. Comes from the top with the lack of clarity on strategy that sees a high-line defender recruited to play next to a penalty-box defender.
The other problem was running him into the ground before and after the Euros. He got next to no recovery time and was selected repeatedly early in the season, despite continuing to make mistakes due to his nervous system and decision-making abilities being totally fried.