Arsenal new signing Lucas Perez poised to make his debut

Arsene Wenger could hand debuts to Shkodran Mustafi and Lucas Perez against Southampton. 

The pair completed moves to the Emirates before the end of the window and have trained this week. 

Mustafi provided a scare during the recent international break but returned unscathed and is likely to replace Rob Holding at the heart of Arsenal's defence. 

A place on the bench is likely for Perez, with Olivier Giroud expected to return to the starting line-up. 

Aaron Ramsey is unlikely to be risked after his injury problems but Alex Iwobi should be back in the squad.