William Saliba is a doubt for Arsenal's trip to face Chelsea in the Carabao Cup semi-final.
The Frenchman was not involved in the Gunners' FA Cup win over Portsmouth on Sunday, missing out on the squad along with Leandro Trossard.
The pair were left out due to picking up knocks, and it remains to be seen whether Arsenal have them available at Stamford Bridge on Wednesday night.
"Those two are a doubt," Mikel Arteta said at his pre-match press conference.
Arsenal will definitely be without Riccardo Calafiori and Piero Hincapie against Chelsea.
Calafiori has been out with a muscle injury since the Carabao Cup win over Crystal Palace last month.
"He's progressing, but we don't know," Arteta said. "A few weeks, probably, but we don't know exactly yet."
Hincapie, meanwhile, limped off against Liverpool last week.
He has since undergone scans, but Arteta did not provide any clarity on when the defender would be back, saying only "we don't know yet" when asked about a potential return date.
Max Dowman and Cristhian Mosquera have both been out with longer-term ankle injuries.
Dowman's last appearance came in early November against Slavia Prague in the Champions League, while Mosquera has been out for more than a month.
"Both evolving really well, but they are not training yet, so still a few weeks away," Arteta said.
