In the right conditions he's a superb player, but those conditions feel increasingly rare in the premier league.
When we're massively on top, and his role is primarily providing an outlet for the attack to quickly recirculate possession, he's genuinely fantastic. Really underrated passer, particularly between the lines. But only if he's given all the time in the world.
Problem is that he's slow, not actually a defensive player and when we're not controlling possession he's not great.
Just because he plays where Carrick played, doesn't mean he's that similar. Carrick for me was one of the very best in the game at reading play, positioning and dropping into the back 4 when needed. Matic is simply a more attacking player, he's never been a defensive shield and really isn't very good at it. He frequently loses midfielders running past him, doesn't provide a screen on the edge of our box and despite his height isn't particularly good at defending aerial threats in our box.
Still feel this is our most crucial upgrade: if we could get a truly defensive player to hold that base, we'd get a lot more from Pogba and Fernandes.