Not sure what to expect, AC Milan's home record in the CL since 2008 is surprisingly terrible for a team of their calibre - only 3 wins in 12 games, all the wins coming against sides which are minnows, really. Will go for the draw or narrow Arsenal win.
Arsenal are vulnerable and soft centred. This Milan team is sturdier and it's at one of the toughest grounds in Europe. A draw at best IMO though I'd love nothing more than seeing an Italian team stuffed. I remember all too well back in the 80's and 90's how they laughed at the English league, now it's them who are being dominated in Europe.
Mexes ahead of Nesta, midfield of Van Bommel, Nocerino, Seedorf and Boateng, Robinho and Ibra up front.
Gibbs was probably played in the hope that Milan wouldn't attack down the flanks, giving him little defensive responsibility and a chance to create the width that Rosicky in front of him won't. Milan would be smart to ask Robinho to play fairly right sided and try and force Gibbs to defend, he'll inevitably **** up.