Arsenal finally made their mark on the transfer window with a deadline-day blockbuster deal to sign Mesut Ozil from Real Madrid. Yet, while the Germany international will excite fans and add extra invention and star power, Arsene Wenger failed to address areas of the squad that were arguably more in need of strengthening.

The Gunners look particularly vulnerable at center-back where Laurent Koscielny, Per Mertesacker and Thomas Vermaelen are the only established options to fill that position. That Vermaelen is currently out injured makes it even more surprising that Wenger didn’t recruit a central defender. Arsenal are also light up front. It can be argued whether an upgrade was needed on Olivier Giroud, but what is not so easy to dispute is that the options do not look good were the France international to be unavailable for any significant length of time.  

Here are four players who Wenger may target when the next transfer window opens in January.

Ashley Williams (Swansea City)

Arsenal were linked to the Swansea and Wales captain throughout the summer, but, according to his club’s chairman, Huw Jenkins, no bid was made. It is believed that Swansea’s £10 million valuation for Williams was the reason for Arsenal’s hesitation. It is easy to see why that would be the case with Williams having just turned 29. Yet, he has now proven himself in the Premier League and has the leadership skills that would benefit Arsenal’s occasionally still-unorganized back line. If injuries or loss of form strike any of Arsenal’s current central defenders, it would be unsurprising for Arsenal to renew their interest.

Micah Richards (Manchester City)

The England international has been repeatedly cited as an Arsenal target in recent years. Richards has played most of his career at right-back, but also had a successful spell playing in the center of a back four. That versatility may appeal to Wenger with Bacary Sagna having suffered two serious injuries in the past two years and with his contract still set to expire at the end of the season. Richards looks unlikely to oust Pablo Zabaleta from the City team and would surely be tempted by a mid-season move if it increases his chances of featuring at next year’s World Cup.

Abel Hernandez (Palermo)

There were strong reports on deadline day that Arsenal had made Palermo striker Hernandez a prime target to add competition for Giroud up front. With Palermo having been relegated to Serie B, it certainly seems possible that a deal could materialize. Hernandez has had a tough time with injuries in recent seasons and has not fulfilled the potential that many observers spoke about when he arrived from Penarol in 2009. In that sense, his signing would certainly carry some risk. If Palermo are struggling to earn a return to Serie A come January, then they could be prepared to allow the 23-year-old to depart.

Christian Benteke (Aston Villa)

After a debut Premier League season in which he fired 19 goals, there were several disappointed clubs when Benteke decided to withdraw his transfer request at Aston Villa and instead sign a new contract. But, as that showed, things can change quickly and it is conceivable that the powerful Belgian striker will soon get itchy feet once more. Benteke has started this season in a manner strongly suggesting that his form last term far from represented merely a "one-season wonder," perhaps meaning that clubs like Arsenal will be more convinced to shell out roughly £25 million to land the 22-year-old.

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