Henrikh Mkhitaryan has been ruled out for six weeks after sustaining a fractured metatarsal in his right foot, Arsenal have announced.
Armenia international Mkhitaryan was substituted at half-time in Arsenal's 2-0 EFL Cup quarter-final defeat against Tottenham at Emirates Stadium last Wednesday.
The 29-year-old received treatment following a tackle from Lucas Moura in the 30th minute but saw out the rest of the half.
However, Mkhitaryan sat out the Gunners' 3-1 victory over Burnley on Saturday and is not anticipated to return until February.
The midfielder will miss clashes with Premier League leaders Liverpool and Chelsea, while Arsenal's meeting with Manchester City on February 3 is likely to come too soon.
We move to at the back with Lolo joining Sokratis and Granit in defence made way for our captain at half-time0-1 (46)December 19, 2018
Unai Emery's defensive troubles continue with Nacho Monreal a doubt to face Brighton and Hove Albion on Boxing Day due to a right hamstring issue that forced him off in the first half against Burnley.
However, Shkodran Mustafi is expected to return to full training this week, having missed Arsenal's last four outings due to a hamstring injury.
