Arsene Wenger has revealed that Arsenal defender Mathieu Debuchy dislocated his shoulder during the club's 3-0 Premier League win against Stoke on Sunday.
Debuchy, 29, collided with Stoke's Marko Arnautovic and clattered into the advertising boards on the side of the pitch. After five minutes being treated by medical staff, he was carried off on a stretcher and replaced by Hector Bellerin in the 13th minute at Emirates Stadium.
Wenger said: "He has a dislocated shoulder. It is difficult (to say how long he will be out) -- you need a diagnosis from a specialist.
"We don't know yet, but he will certainly not play next week. Kieran Gibbs still has an inflamed ankle.
"Monreal and Debuchy can play centre-back, but if Gibbs is not here Monreal cannot play centre-back and if Debuchy is not here he cannot play centre-back. This is a position where we are short.''
The Frenchman had only recently returned after missing three months of the season with a serious ankle injury. Calum Chambers and Bellerin deputised at right-back, but the latest injury could force Wenger's hand into the transfer market.