Arsenal manager Mikel Arteta has said Ezri Konsa picked up a knock in their 2-1 victory over Slavia Prague in the Champions League on Wednesday night.
Konsa was forced off with a knee injury during the second half of the match.
The England defender started the game alongside Gabriel Magalhaes in central defence.
He was replaced by Cristhian Mosquera after picking up the injury, with fit-again William Saliba also on the bench.
"He is obviously playing a lot; he’s played so many games in the last few weeks," Arteta said of Konsa after Arsenal’s win in Prague.
"He had some issues, and we decided to take him off."
Konsa could now be a doubt for Arsenal’s next game at home to Hull City in the Premier League on Saturday.
UCL: Arteta reveals Arsenal injury blow after Slavia Prague win