Arsenal forward Danny Welbeck will be out until after next month's international break with a groin injury sustained against Chelsea on Sunday.
Welbeck will miss Wednesday's Carabao Cup clash with Doncaster, the Premier League games with West Brom and Brighton and the Europa League tie at Bate Borisov of Belarus.
Boss Arsene Wenger told arsenal.com on Tuesday: "Danny has a scan today. We don't know how bad his groin injury is but he will certainly be out until the international break."
Arsenal's first game after the internationals is against Watford on October 14.
Playmaker Mesut Ozil, midfielder Francis Coquelin and full-back Mathieu Debuchy will also be absent on Wednesday.
Midfielder Jack Wilshere played his first Gunners game in over a year in last week's Europa League win over Cologne.
Ozil remains sidelined with the knee problem which meant the German missed the trip to Chelsea.
Wenger said: "Mesut is training again, but for (Wednesday), no (he will not feature). He has a little inflammation of his knee."
Defender Calum Chambers will be included against Doncaster.
"It will be a similar team to the one that played against Cologne," Wenger added.
Goalkeeper David Ospina, club captain Per Mertesacker, Mohamed Elneny, Ainsley Maitland-Niles, Theo Walcott, Alexis Sanchez and Olivier Giroud all started against Cologne before dropping out of the starting line-up for Sunday's draw at Stamford Bridge.
Wenger's priority against Doncaster will be to build on the morale-boosting point and performance at Chelsea, where Arsenal had lost on five previous visits, and carry momentum into the West Brom contest.