The Chilean has spent almost two months out with injury and last featured for the Gunners at the end of November.
Arsene Wenger makes just the one change to the side that were held to a goalless draw at Stoke City last time out, with Mesut Ozil recovering from a foot injury to rejoin the starting XI at the expense of Alex Oxlade-Chamberlain.
For the visitors, Eden Hazard is named on the bench after missing the last three matches with a groin injury, while Diego Costa shakes off a bruised shin to lead the line once again.
Interim manager Guus Hiddink makes just one tweak to the side that scraped to a 3-3 draw with Everton, bringing Oscar back into the fold in place of Pedro.
Arsenal: Cech; Bellerin, Koscielny, Mertesacker, Monreal; Flamini, Ramsey, Campbell, Ozil, Walcott; Giroud
Subs: Ospina, Chambers, Gibbs, Gabriel, Elneny, Oxlade-Chamberlain, Sanchez
Chelsea: Courtois; Ivanovic, Zouma, Terry, Azpilicueta; Mikel, Matic; Willian, Fabregas, Oscar; Diego Costa
Subs: Begovic, Cahill, Baba Rahman, Loftus-Cheek, Traore, Hazard, Remy
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