The disappointment around the Emirates Stadium at Arsenal’s exit from the Capital One Cup at the hands of Southampton on Tuesday evening may be short-lived, but the lack of squad depth that was exposed in the 2-1 defeat could have more serious consequences. In particular, Arsène Wenger was compelled to select a makeshift defense, featuring debutante Isaac Hayden, two 19-year-olds in Héctor Bellerín and Calum Chambers as well as Francis Coquelin playing out of position. Having made the decision not to replace the departed Thomas Vermaelen in the summer, Arsenal was left with six established defenders once the transfer window shut. Two of those -- Mathieu Debuchy and Nacho Monreal -- are now out injured.

Unsurprisingly then, Arsenal continues to be linked with central defenders to strengthen its squad when the transfer window reopens in January. According to the Daily Express, Aston Villa’s Ron Vlaar has been a target and was even the subject of a deadline-day inquiry at the start of September. Vlaar was heavily linked with a move away during the summer as he entered the final year of his contract and enjoyed a fine World Cup with the Netherlands. Manchester United, managed by former Netherlands coach Louis van Gaal, was strongly linked, but it now seems that the 29-year-old could be staying at Villa Park. Aston Villa is reportedly set to open talks with Vlaar over a new deal, with the center-back thought to be open to the prospect of staying.

Vlaar’s age and his physical style always made him a somewhat unlikely target for Wenger. Instead, Arsenal may be targeting a younger central defender. That is the belief of the Daily Star, which reports that Fabian Schär’s signature will be fought over by north London rivals Arsenal and Tottenham in January. Schär, 22, has seen his reputation soar since joining Basel in 2012, and he is now a regular in the Switzerland squad. He is said to be valued at £10 million, despite being out of contract next summer.

It is a similar scenario for a player linked more frequently to Arsenal than any other in recent months. Arsenal was thought to be close to concluding a deal for Sami Khedira in the summer before balking over his wage demands. Khedira has since declined the chance to extend his contract amid speculation that Bayern Munich is keen to take him on a free transfer at the end of the season. In recent days, though, speculation has been making the rounds that Arsenal had sewn up a £11 million deal to bring the German World Cup-winning midfielder to Arsenal in the summer.

While several outlets have picked up on the story from website Caught Offside, at this stage there appears little substance behind it. Unless a club makes a major offer to Khedira, he is likely to bide his time until the summer, when he will be able to have his pick of clubs and reap greater financial rewards from a free transfer.

Arsenal may instead have another central midfielder in its sights for January. According to the Daily Mail, Arsenal is now ready to make an approach for 19-year-old Adrien Rabiot, with Paris Saint-Germain said to be willing to listen to offers of around £5.6 million for a player who has also entered the final year of his contract. Rabiot was linked with Arsenal, as well as Serie A giants Juventus and Roma over the summer. The France Under-21 international will also be able to sign a pre-contract agreement with another club in January.