Arsenal take on Southampton at the Emirates in their fourth Premier League game of the 2016-17 campaign.
Gunners boss Arsene Wenger will give Shkodran Mustafi and Lucas their full debut against the Saints.
Mustafi will start in defence while Lucas has been deployed as first-choice striker while Olivier Giroud starts on the bench.
The Germany international made the move to Arsenal from Valencia for a £35 million transfer fee according to the BBC. Gunners boss Wenger was keen to sign a defender after both Mertesacker and Gabriel picking up long-term injuries.
Arsenal star Mesut Ozil will start however, Alexis Sanchez will be on the bench after recently returning from international duty in South America.
The Gunners could move as high as 4th place in the Premier League table with a victory.
Arsenal v Southampton
Kick-Off: 15:00 GMT
Arsenal confirmed XI: Cech, Mustafi, Koscielny, Bellerin, Monreal, Cazorla, Coquelin, Walcott, Ozil, Chamberlain, Lucas
Subs: Ospina, Holding, Elneny, Xhaka, Iwobi, Alexis, Giroud
Southampton: Forster, Cedric, Clasie, Fonte, Davis, Rodriguez, Tadic, Romeu, Van Dijk, Bertrand, Redmond
Subs: McCarthy, Yoshida, Long, Austin, Ward-Prowse, Hojbjerg, Targett
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