Despite winning against Liverpool on Saturday, Arsenal suffered several injury problems, with Mikel Arteta getting knocked out, his substitute Abou Diaby getting substituted, and Kieran Gibbs and Yossi Benayoun also picked up minor knocks.
French radio RMC were reporting that Diaby had come off with a thigh twinge, but according to Arsene Wenger, the midfielder has a hamstring problem. Given his history of injury problems, especially this season, that is likely the last time Diaby plays all season, which is a shame, because he offered drive from midfield, and also because Arsenal have no fit midfielders left, as Rosicky and Song are also carrying knocks.
Yossi Benayoun, having not played a lot of football before playing full games Sunday and Wednesday also picked up a small hamstring problem, while Kieran Gibbs also picked up an unspecified injury. The Gibbs injury is less problematic if it's not long term; Carl Jenkinson can fill in at left back, and while it's not ideal, it's better than having to play Sebastien Squillaci at centre back and Thomas Vermaelen at left back.
There is also better news on Mikel Arteta; the midfielder was taken to the hospital with concussion, and it seems that he's alright to travel, having left the hospital to return with the Arsenal team on the train back to London.
Hopefully, Arteta will be back in a couple of weeks, though concussion is something that takes different periods of time for different people. In the short term, Arsenal have a major problem in their midfield, especially for Tuesday night. The next Premier League game is on Monday, March 12th, so Benayoun, Rosicky and Song should all have recovered by then if they were to not be played in Tuesday's dead-rubber.