It has been a mixed season for Arsenal so far, mixing famous victories against Chelsea and Borussia Dortmund with lame, cringing defeats to the likes of Blackburn and Swansea. The team as a whole has become less mistake-prone than that of last season, with the defense becoming a lot tighter. Laurent Koscielny in particular is worthy of praise in this case. However, injuries have struck the squad and Arsenal are now looking for replacements in two key areas.
1) At full-back
With Bacary Sagna and Carl Jenkinson injured at right-back, and Andre Santos and Kieran Gibbs injured at left-back, Arsenal have had to play two central defenders in those positions, a move that has often cost them games, so a loan or a purchase of a top full-back or two is definitely on Arsene Wenger's agenda for January.
2) At striker
In this position, Robin Van Persie has been the shining light for an Arsenal, creating and scoring aplenty. So much so that Arsenal have been called a one-man side this season. While that accusation is not entirely accurate, it cannot be denied that Ju Young Park or Marouane Chamakh are not adequate replacements at this moment in time for Van Persie's goal threat.
Arsenal will be looking for a top striker who can create as well as score goals all by himself, preferably one who is versatile, with European experience, and one who can head the ball as well as play as a lone striker in a 4-3-3. A Robin Van Persie replacement, in short.
Move aside, Mario Gotze, the Polish poacher has something to offer that he doesn't. With 12 goals this season, and five assists, Lewandowski has the same number as Gotze, while scoring seven more goals than him. Lewandowski's style is quite reminiscent of another Polish striker, Miroslav Klose. He is the definitive/target man poacher combination, who can both get goals and create them with flick on passes. His finishing ability is sublime, and his balance helps him substantially in this case.
Also able to play in a 4-2-3-1, which Arsenal are adept at playing, he seems to fit into the Arsenal system, with a role that mimics that of Marouane Chamakh last season, flicking on for two creative inside forwards. However, Arsenal have moved on to a more direct system of play, which might not suit him. However, he is a good, proven goalscorer, who definitely has ability.
Moussa Sow is another target man/heavyweight striker who is adept at playing physically as well as technically. According to many France football experts, he made the difference between Lille and Marseille last season, scoring more than 20 goals.
He is practised at playing a 4-3-3 formation with creative talent behind him but with less finishing ability. In that respect, Lille have to rely on Sow and Eden Hazard to provide goals for the rest of the Lille side. This season, Lille have been playing similarly to Arsenal, playing a more direct game than they're used to, with Payet and Hazard giving in a lot of crosses.
Olivier Giroud has been the surprise of Ligue 1 this season, making the difference for high-flyers Montpelier. He is another target man who likes to flick on and play short passes to wingers or second strikers running, and he could possibly fit in well and play Arsenal's system, as mentioned before.
Giroud has 14 goals and five assists this season, the highest in Ligue 1 and only four goals behind the total of Robin Van Persie. He has led one-man shows against Sochaux (scoring all three of Montpellier's goals) as well as against Lorient (scoring one and assisting the rest of Montpellier's goals).
The Schalke full-back is one of the most potent attacking forces in German football, scoring two and assisting on three this season. He is also competent defensively, being particularly adept at ball interception. He is also very consistent.
Aly Cissokho is a very competent Lyon full-back who can work both offensively and defensively. He is accustomed to pace and is very physical in his style.