It's already been a difficult season for Arsene Wenger, and he may need major reinforcements in January. Reuters

With Arsenal continuing to struggle in the Premier League, early attention is being paid to the January transfer period where the Gunners can get some much-needed relief at some key positions.

Manager Arsene Wenger will have two important players return before he can start searching for reinforcements. Midfielder Jack Wilshere is expected back in late October, and Thomas Vermaelen should return to action in the middle of October.

Still, it would be prudent for Wenger to start looking for another centre back as well as a holding midfielder, and perhaps another versatile midfielder. There will be plenty of options through transfers and loans.

Though Wenger brought in lanky German Per Mertesacker in August to strengthen the central defense, Vermaelen has proven to be injury prone, while Laurent Koscielny and Johan Djourou have been inconsistent.

Over the past three weeks, there has been little mention of adding a centre back. Bolton's Gary Cahill and Blackburn's Christopher Samba are probably still on Wenger's radar, but the asking price for both players might still be too high for the Gunners.

Everton's Phil Jagielka would have been the ideal addition. The England star is capable of playing both centre back and defensive midfielder. At the moment, Alex Song is the regular defensive midfielder with Emmanuel Frimpong and Francis Coquelin as the primary backups.

Arsenal appear to be well covered at left back with Andre Santos and Kieran Gibbs. Vermaelen is also capable of playing left back. It's possible Wenger would pursue a right back as Carl Jenkinson is only 19, and may not be best option behind Bacary Sagna.

According to Daily Mail, Arsenal are prepared to make a £10 million bid on midfielder Juan Manuel Vargas of Fiorentina. The versatile Peruvian is effective on the left side, and is excellent at crossing the ball, and plays solid defense.

Should Arsenal miss out on Vargas, Inter Milan winger Ricky Alvarez could be available on a loan. The 23-year-old Argentine has seen limited action with Inter, so it is reasonable for Inter to consider loaning him to Premier League club.

Everton's Marouane Fellaini may follow midfielder Mikel Arteta to Arsenal after manager David Moyes admitted he might be forced to sell, according to Metro. The 23-year-old box-to-box midfielder already has 29 appearances for Belgium, and might be a great asset to the Gunners because of his stamina.

Fiorentina forward Stevan Jovetic has delayed signing a new contract, so Arsenal might consider the young Montenegrin to perhaps fill in for veteran Andrey Arshavin. Jovetic is one of the most coveted young attacking players in Europe.

The Sun reported that Arsenal might consider Real Madrid attacking midfielder Esteban Granero. The 24-year-old Spaniard is valued at about £10 million.

At the moment, Arsenal are languishing in the Premier League with only one win and own draw in five matches. New players like Chu Young Park and Yossi Benayoun are still getting their feet wet, but Arsenal are already in a deep hole in September.

Though it may be premature to consider major changes as Wilshere and Vermaelen make their return from injury next month, and with midfielder Aaron Ramsey showing promise in limited action, Wenger still needs to explore ways to bolster this club or risk falling out of contention for next season's Champions League.