​​Arsenal head coach Unai Emery has admitted that the club may need to buy a new centre-back in the January transfer window in order to boost their defensive options, following injuries to a number of key players at the back.

The Gunners are currently short of defenders after Rob Holding was ruled out for the rest of the season with a torn knee ligament while Luarent Koscielny has only recovered from an Achilles injury which saw him miss the first half of the campaign.

However despite the news that the Frenchman is set to return, there are doubts whether Koscielny will be able to be fully relied upon, considering that he is 33-years-old and is coming back from an injury after seven months out of the game.

"If we can take one player to help us at centre-back, I think it's a good option. But a transfer is not easy," Emery said.

​According to ESPN, the Gunners are interested in signing either Manchester United's Eric Bailly or Chelsea defender Gary Cahill as a potential replacement for Holding, though nothing has been made official on the same as yet.

Arsenal are currently on a 21-match unbeaten streak in all competitions and will next be seen in action when they face Qarabag in the UEFA Europa League on Thursday.