1. Nicolas N'Koulou
The Cameroonian centre back was linked with a host of clubs during the summer transfer window, indeed Arsenal were rumoured to be tracking N'Koulou closely. Marseille's second place finish and Champions League football seem to have been enough to keep N'Koulou at the club for now. Marseille's centre back will be tasked with containing the inform Olivier Giroud, who has already found the net 5 times this season. However the Cameroonian will be more than up for the challenge. N'Koulou is strong, quick and like most modern centre backs comfortable on the ball. Consequently Giroud should expect his toughest battle of the season so far on Wednesday night. N'Koulou is someone who revels in the physical side of the game and as such Arsenal's strikeforce must be prepared to ride the occasional strong tackle. Furthermore, despite only being 6ft N'Koulou possesses a phenomenal leap, making him a powerhouse in the air. N'Koulou is the rock at the heart of Marseille's defence and, if Wenger's side want to continue their goal scoring exploits, they will have to find a way past the formidable Cameroonian.