Source: PA
Walcott winning cup fitness battle
Arsenal winger Theo Walcott is expected to recover from a slight hamstring strain for the FA Cup tie at Leyton Orient.
Centre-back Johan Djourou is also likely to be included in the squad if he recovers from a back problem he suffered against Barcelona in midweek.
Right-back Bacary Sagna is available after returning from suspension but midfielder Abou Diaby is still banned.
Striker Marouane Chamakh will return to the squad after missing out against Barcelona.
