Arsenal have been handed a blow in the packed festive season after midfielder Henrikh Mkhitaryan was ruled out of action for up to six weeks with a fractured metatarsal in his right foot.
Mkhitaryan, 29, was replaced at half-time during the Carabao Cup quarter-final loss to Tottenham and missed the Premier League win over Burnley.
The Armenian has scored four goals and provided three assists for the Emirates Stadium side this season.
He joins a lengthy injury list for Arsenal that also includes long-term absentees Danny Welbeck and Rob Holding, with both not expected to feature until next season.
Defenders Hector Bellerin and Shkodran Mustafi are both out of the Boxing Day fixture at Brighton but left-back Nacho Monreal will undergo a late fitness test.