Thing is about Maguire, alright, he's slow and hasn't played much this season, but he's training with the squad. He should know his role and be able to execute it, to a greater or lesser extent. However, he looks like little boy lost, no clue what to do or where he's supposed to be.
I mean, Ronaldo may not be the player he was and doesn't have the pace he used to, but you can see he's trying to do what he's been coached to do in the system.
Elanga has hardly played and isn't that good, but he's pressed well and it's clear he knows his role.
Doesn't Maguire attend the coaching sessions, doesn't he train with the other defenders? Why doesn't he know what his role is? Even if he might not be able to do it that well, he must, at least, know what he's supposed to be doing, surely?