Olivier Giroud has had to be substituted with a suspected hamstring injury during Arsenal's 1-0 win over West Ham United in the EFL Cup.
The French striker limped off the pitch after pulling up with the issue with just 13 minutes remaining in the quarter-final clash at the Emirates Stadium.
Giroud, who has had little first-team action this season but started Tuesday night's game, put his head in his hands and appeared distraught as he was immediately replaced by Reiss Nelson.
Should the 31-year-old face an extended spell on the sidelines, Arsene Wenger will only have one fit out-and-out striker in Alexandre Lacazette upon which to call.
Arsenal booked their place in the last four of the competition at the expense of David Moyes's side thanks to Danny Welbeck's close-range goal shortly before half time.
