After a sobering first five months of the season in which the signings of Danny Welbeck and Alexis Sanchez have failed to yield a title challenge, Arsene Wenger must act decisively in January – not something he's known for – to keep the club's Champions League charge alive. Resources in defensive areas are urgent to say the least.
What they need
Though Wenger has had six senior defenders to choose from this season, injuries and untimely suspensions have meant Arsenal have often only had half of those available. It's hard to think of another Premier League team more wafer-thin at the back, while in defensive midfield problems continue despite Francis Coquelin's recent recall, with Mikel Arteta constantly injured and Mathieu Flamini out of form.
Who could join?
Southampton's Morgan Schneiderlin goes into the January window as the primary target for Arsenal, after coming close to joining north London rivals Tottenham Hotspur during the summer. Celtic centre-back Virgil van Dijk has flirted with the idea of moving to the Gunners, while Real Madrid full-back Fabio Coentrao may also be pursued.
Who could leave?
Several players have become disillusioned with life at The Emirates Stadium, particularly in attacking areas where Sanchez and Welbeck have monopolised appearances in the first team. Lukas Podolski will almost certainly leave, while Joel Campbell and Yaya Sanogo could depart on loan. Tomas Rosicky is another player who faces the axe, while Abou Diaby could be offloaded should the club decide against a new contract.
What the manager has said
"I would like to remind you that to buy football players is not to go into a supermarket and just say: 'I want to buy a right-back or a centre-back,'" Wenger says.
"It's to find the right quality. If you go out tomorrow, you will see that everybody looks for the same positions everywhere. It's not as simple as it looks.
"In January, it is even more difficult because players are even less available than in June or July. But we will try to be creative and have one or two good ideas."