Arsenal have confirmed they will be without defender Gabriel for at least six weeks due to an ankle injury ahead of their Premier League season opener against Liverpool.
The Gunners have been rocked by injuries to their defenders during pre-season with Gabriel joining that list after he was stretchered off in a pre-season friendly against Manchester City.
Per Mertesacker is not expected to return until the new year after a knee injury forced him to undergo surgery, while Laurent Koscielny has had no pre-season campaign after his extended summer break following France's Euro 2016 campaign.
Wenger's options now consist of Calum Chambers and summer signing Rob Holding, while midfielders Krystian Bielik and Francis Coquelin have trained at centre-half during the summer. Full-back Nacho Monreal could also be considered.
"Gabriel has an ankle problem and he will be out for six to eight weeks," the Gunners boss confirmed. "It is a bit better than we feared at the start. Carl is doing well, and he should be back in November. He is on schedule for his return."
Jack Wilshere, who started just one game last season due to injury, sparked more fitness fears when a knee problem saw him miss the final stage of the club's pre-season tour. Wenger has calmed fears of yet another long-term problem for the England international however and suggests he could even have a role to play off the bench against Liverpool on Sunday.
"Jack is doing well, but he will be short for Sunday. He is back in training but will not be completely ready for Sunday."
Mertesacker and Danny Welbeck remain long-term absentees and are not expected to return until 2017.
"We had very good news on Danny's latest scan and Per is at the moment off his feet for three weeks, so of course it is a bit boring for him. He is with his family in Hannover, but on the football front he is very frustrated. We think it will be four to five months for both players."