He's 30, and not the force he once was, plus injury prone. He will need game time, though, and I can't see Carrick being dropped. Will he play second fiddle?
If we shift to the 3-5-2 again, he could be a regular starter, and add steel to the midfield.
--------------------------------------------Valdes----------------------------------------- : Lindegaard/Cech
-----------------Otamendi------------Smalling-------------Rojo-------------------- : Jones/McNair/Evans/Shaw
--------------------------------Carrick-----------Schweini----------------------------- : Blind/Herrera/Fellaini
---Valencia-----------------------------Mata---------------------------Depay-------- : Young/Januzaj/Shaw
-------------------------------Rooney----------Di Maria------------------------------- : RvP/Wilson