On this evidence, he surely has a case to force his way into his manager's plans - not least because he possesses the style and composure to bring the best from United's £89 million world record signing Paul Pogba.
Pogba has looked restricted in his early performances and the selection of Carrick, so reliable and intelligent in possession (even chipping in with a goal at Sixfields), would allow the Frenchman freedom, to play to his strengths and give the opportunity to do damage further forward.
Carrick's experience and excellence in reading the game adds to Mourinho's options and could finally get the best out of our showpiece summer signing.
From what we have seen so far, a Pogba-Fellaini axis looks incompatible so surely Carrick is a certainty to start against Leicester in the league on Saturday.
He's sharper in the mind than any of his Old Trafford colleagues and is the player that can dictate and run a game from deep in the manner Fellaini simply cannot- and neither can Pogba, yet.
He's doesn't run around or charge up and down the pitch, but his awareness, positional sense and clever use of the ball makes his a cunning and dependable presence in the middle of the park.
At the moment Pogba is trying- and failing- to do everything himself.
He needs to be rid of defensive responsibility- give him a free role in behind Zlatan Ibrahimovic - that is far better than a free role in front of his back four.
It is there that Pogba will flourish.
With Carrick and Ander Herrera impressive at Northampton and with a host of attacking options available to Mourinho, will Wayne Rooney's place against Leicester at Old Trafford at the weekend come under threat from one of his more in-form team mates?
Pogba and Zlatan Ibrahimovic were given the night off as Mourinho made nine changes from the defeat at Vicarage Road but there was no respite for Rooney.
United's embattled skipper, who has bore the brunt of much criticism aimed at the team this term, as in the starting line-up as a striker but endured another frustrating outing.
Nothing seems to be working for our captain.
He missed a relatively straightforward header early on and, when he did hit the target after Tim Fosu-Mensah had hit the bar, he was adjudged to have been offside.