I think it will be Kos-Djourou (who have been good and are not getting the credit they deserve) Vermaelen may be back in time for the second leg (according to Mr. Wenger's updates) but i doubt it, if Vermaelen and Van Persie are fit i'd give us a much better chance of progressing, in an ideal world our team would be
Szczesny
Sagna - Djourou - Vermaelen - Clichy
Wilshere - Song
Walcott - Fabregas - Nasri
Van Persie
That would be a dream.
That's pretty much the team that beat Chelsea. Wilshere and Walcott are really starting to make Arsenal a lot better everytime they play. I haven't seen that team fail. Its when Arshavin, Eboue and Chamack come in that there's problems.