Manager Arsene Wenger made nine alterations for the Europa League win over Cologne but the likes of Petr Cech, Mesut Ozil, Laurent Koscielny, Aaron Ramsey and Alexandre Lacazette will all return to the squad at Stamford Bridge.
Sanchez will feature after playing the whole game on Thursday night, where Theo Walcott (calf) hobbled off. Francis Coquelin (hamstring) and Santi Cazorla (ankle) are definitely out.
Sead Kolasinac is expected to start at left-back after making a huge impact from the bench in the win over Cologne, the Bosnian scoring the equaliser as the Gunners fought back to win the European clash 3-1.
Wenger says the introduction of the summer signing, who has now registered two goals and two assists since moving from Schalke, was vital in turning the game around.
“I moved to a four [at the back] in the second half and Kolasinac gave us a lot going forward, but as well he pushed Sanchez more forward,” said Wenger. “Sanchez played very deep in the first half and when he had more support on the flanks from Kolasinac he became more dangerous.”
Provisional squad: Cech, Ospina, Mertesacker, Holding, Koscielny, Monreal, Mustafi, Bellerin, Nelson, Kolasinac, Ramsey, Wilshere, Coquelin, Xhaka, Elneny, Ozil, Giroud, Walcott, Sanchez, Iwobi, Welbeck, Lacazette.
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