Granit Xhaka is currently serving a four-match suspension and Mohamed Elneny is still at the Africa Cup of Nations with Egypt.
Santi Cazorla is out for the indefinite future through injury and Francis Coquelin also came away from the Watford game with an injury who Wenger said could be an injury worry.
Arsene Wenger doesn't have one fit central midfielder at Arsenal
Jack Wilshere can't be recalled from his loan
The injury crisis couldn't come at a worser time with no recognised midfielder available for the crucial title match against Chelsea on Saturday (12.30pm).
Meanwhile Jack Wilshere is enjoying a rare injury-free season on loan at Bournemouth.
But The Sun say there is no clause in Wilshere's loan deal that allows Wenger to recall the England international back to Arsenal.
Arsenal fans celebrate Aaron Ramsey injury
Tue, January 31, 2017
Arsenal fans on Twitter weren't too disappointed to see Aaron Ramsey leave the field early…
1 of 11
Arsenal fans on Twitter weren't too disappointed as Aaron Ramsey left injured…
Aaron Ramsey limped off in the 2-1 defeat to Watford last night
Alex Oxlade-Chamberlain has deputised in a central midfield role for Arsenal in the past and Wenger is hopeful he will be fit to face Chelsea.
Wenger said: "He got a kick on his knee, yes.
"No I don't think [he'll be a doubt for the Chelsea game]. I think he should be alright."