The pair were rested for Thursday’s Europa League win over Dundalk, but should return for this huge clash at Old Trafford.
Arsenal are light on bodies at centre-back, with Gabriel, Shkodran Mustafi and William Saliba their only available options for Sunday.
Saliba is still yet to make his Arsenal debut and is therefore unlikely to start, but he could make the bench.
Tierney should form a back-three with Gabriel and Mustafi, while ahead of them Thomas Partey is due to return in midfield after being rested on Thursday.
Bukayo Saka and Hector Bellerin were also given a night off against Dundalk, but look ready to come in as the wing-backs.
Going forward, Mikel Arteta has a debate over what to do. Pierre-Emerick Aubameyang could lead the line, but it is more likely he starts on the left.
Alexandre Lacazette can then play through the middle, with the fit-again Willian expected to play wide right.
Predicted Arsenal XI (3-4-3): Leno; Mustafi, Gabriel, Tierney; Bellerin, Partey, Xhaka, Saka; Willian, Lacazette, Aubameyang
Arsenal squad from: Leno, Macey, Runarsson; Bellerin, Cedric, Gabriel, Kolasinac, Mustafi, Saliba, Tierney; Ceballos, Elneny, Maitland-Niles, Partey, Saka, Smith Rowe, Willock, Xhaka; Aubameyang, Nelson, Nketiah, Lacazette, Pepe and Willian
Injured: Holding (hamstring), Luiz (thigh), Mari (ankle) and Martinelli (knee)
Date and time: Sunday, November 1 at 4.30pm
TV: Sky Sports Main Event and Premier League
Last meeting: Arsenal 2-0 Manchester United
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