Mertesacker has been struggling with a minor gluteus problem, while Gibbs had been suffering with a hamstring injury – but both are available for selection for the clash at Emirates Stadium.
Wenger said on Friday: “Mertesacker is available for the weekend. He has normal training today and I don’t think there will be a problem.
“[Mathieu] Flamini is back in the squad. Gibbs is alright.”
The Arsenal boss also confirmed that Nacho Monreal remains sidelined with a back problem ahead of the visit of the Lilywhites.
Arsenal head into Saturday’s game looking to make it back-to-back Premier League wins for the first time this season after their victory at Aston Villa last weekend.
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