Arsenal manager Arsene Wenger has called upon Argentine goalkeeper Emiliano Martinez to start against West Ham.
The 24-year-old has not played in the Premier League since the 2014-15 season, but is named in the starting XI due to injuries to Gunners goalkeepers Petr Cech and David Ospina.
Gabriel and Mohamed Elneny come into the side that drew 2-2 with Manchester City, replacing injured duo Francis Coquelin and Laurent Koscielny.
There is also a surprise appearance on the substitutes bench for goalkeeper Matt Macey after the 22-year-old was recalled from his loan spell at League 2 side Luton Town.
Theo Walcott captains the side amid reports that the Gunners broke Premier League regulations by failing to nominate a captain when Koscielny came off injured against City on Sunday.
Arsenal: Martinez, Bellerin, Gabriel, Mustafi, Monreal; Xhaka, Elneny; Walcott, Ozil, Sanchez; Welbeck.