For PES? It's a 4-3-3. Sagna and Clichy/Gibbs play wing back instead of just right and left back and they line up slightly more advanced than Gallas and Vermaelen. Song is in the middle dropped back a little behind the circle as a holding midfielder, Nasri or Diaby on the left, Fabregas on the right (perhaps slightly more forward than the left midfielder), Arshavin on the left wing and Walcott/Eduardo/Benny on the right wing, both of those guys at about 3/4 field, and then RVP at centre field in the most advanced position. So 4 defenders than a circle shape with the six midfielders and fowards.
The formation was a little mixed today: Sagna--Gallas--Vermaelen--Gibbs -------------------------------- -------------Diaby-------------- -------------------------------- -------Ramsey----Fabregas----- -------------------------------- ---Arshavin----------Eduardo--- -----------van Persie-----------
