Emiliano Martinez starts in goal for Arsenal against West Ham as David Ospina failed to make the cut, while Michail Antonio starts for the Hammers at Emirates Stadium.
Ospina required treatment after a clash with Nicolas Otamendi in the second half of Sunday’s 2-2 draw with Manchester City at the Emirates, and his absence - along with No.1 goalkeeper Petr Cech - means third-choice Martinez steps in at late notice.
Slaven Bilic has been boosted by the return of key man Antonio, who starts in midfield for the Hammers.Mark Noble and Arthur Masuaku also make Bilic's XI, with Diafra Sakho on the bench.
Arsene Wenger has gone with a pacey attack, allowing Danny Welbeck to lead the line with the striker supported by Theo Walcott, Mesut Ozil and Alexis Sanchez.
Arsenal starting XI: Martinez, Bellerin, Mustafi, Gabriel, Monreal, Elneny, Xhaka, Walcott, Ozil, Sanchez, Welbeck
Subs: Macey, Mertesacker, Gibbs, Ramsey, Oxlade-chamberlain, Iwobi, Giroud
West Ham XI: Randolph, Byram, Collins, Fonte, Masuaku, Kouyate, Noble, Antonio, Lanzini, Ayew, Carroll
Subs: Adrian, Nordtveit, Fernandes, Feghouli, Snodgrass, Sakho, Calleri