Arsène Wenger has revealed that Arsenal are working hard to sign a defender during the January transfer window. Only weeks after stating it was the center of his midfield that was his priority to reinforce this month, a fresh injury blow to Mathieu Debuchy has compelled the Arsenal manager to focus on strengthening what was already a wafer-thin backline.

“We are out on the market and we work very hard for every day,” he said at his press conference ahead of Arsenal’s trip to Manchester City on Sunday. “All our scouts, all out people are working very hard to find a defender. At the moment we are more looking for the defensive department.”

Debuchy, who only returned from a lengthy absence last month, has been ruled out for three months after undergoing surgery for a dislocated shoulder suffered against Stoke City last week. His absence leaves Wenger having to depend on 19-year-old’s Calum Chambers and Hector Bellerin to occupy the right-back slot and, along with left-back Nacho Monreal, provide cover in the center of defense.

Arsenal have been linked to a number of central defensive targets, none more so than West Ham United’s Winston Reid. The New Zealand international is in the final six months of his contract at Upton Park, with manager Sam Allardyce resigned to losing him at the end of the season. While Allardyce doesn’t see the value of cashing on him this month, he was unable to rule it out entirely should a big offer come in. Whether Arsenal are prepared to sanction such a bid is doubtful, although Wenger did not rule it out when asked on Friday.

As well as Reid, Arsenal have consistently been credited with an interest in Celtic center-back Virgil van Dijk, The Dutch 23-year-old has continued to impress with the Scottish champions since arriving from Groningen in the summer of 2013. While there has been no confirmation of any approach on Arsenal’s end, Van Dijk has revealed he is flattered to be linked with the Gunners, although he is not expecting Celtic to make a move straightforward in the January transfer window.

“I have recently been thinking a bit about it [his career],” he told Dutch publication De Telegraaf, reports Metro. “I am now 23 and have played at Willem II, FC Groningen and Celtic and am now linked to clubs like Arsenal. Isn’t that great?

“There are a lot of clubs interested, but Celtic is holding onto a big transfer fee. The club is clear: they don’t want to let me go in the winter, because we’re playing for four trophies. I understand the point of view from the club and I see it as a compliment that they don’t want to let me go. But we have to be realistic. If there’s a nice club from England, we have to talk. I want to develop myself as a player, that’s for sure.”

A new target has also emerged in recent days. Both the Daily Mirror and the Daily Mail have reported that Arsenal are keen on Espanyol defender Hector Moreno, with the latter publication stating that the Gunners had a scout present to watch him in action on Tuesday. Moreno, 26, has proved to be a quality operator at the heart of the defense in La Liga and for the Mexico national team.

The urgency to sign a defender, coupled with Francis Coquelin’s solid performances since returning from a loan spell, appears to have taken the focus away from signing a midfielder. Arsenal are also set to unveil the signing of Polish midfielder Krystian Bielik, with Wenger confirming that he was having a medical with the club on Friday ahead of a proposed transfer from Legia Warsaw. Still, aged just 17 and with only six first-team appearances, Bielik is unlikely, though, to be an immediate option for Arsenal’s senior side. Arsenal have been strongly linked with Borussia Dortmund midfielder Ilkay Gundogan, but Wenger’s response when asked about the rumors on Friday was “He’s not a defender.”