Michael Carrick has to start if Manchester United are to beat Arsenal this weekend, according to Ray Wilkins.
The former United star says defeat in Saturday's live Sky Sports game - even this early in the season - would end his old club's hopes of a top-four Premier League finish.
Wilkins believes starting veteran midfielder Carrick represents Jose Mourinho's best chance of continuing an impressive head-to-head record against Arsene Wenger.
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Wenger's sole success against Mourinho came in last season's Community Shield, but victory at Old Trafford would give Arsenal a nine-point lead over United with almost a third of the season played.
Speaking on Sky Sports News HQ, Wilkins said: "Manchester United cannot afford to let Arsenal win at the weekend. Arsenal will bounce clear, and you can't be giving teams three-game swings at his stage of the season.
"For United to finish in the top four they've got to beat Arsenal on Saturday, and it's going to be tough."
Mourinho is without suspended Zlatan Ibrahimovic for the game and has problems in defence with Eric Bailly and Chris Smalling injured.
But the key area, Wilkins says, is in midfield where Carrick was recalled for the 3-1 defeat of Swansea that preceded the international break and gave United a first league win in five games.
Manchester United have won on each of the 35-year-old's four starts this season, and Wilkins said: "I don't think United have controlled many games.
"I think with Carrick in the side that's the only option they have to get some semblance of control and a bit of serenity.
"He sees the game so well, he can hit long passes and if United are going to push up and attack Arsenal you're going to need that guy, with all his knowledge, to stop counter-attacks.
"I think Michael will have to play for United to have a good chance."