That was a 4-2-4 iirc.
--------Buffon------------
Licht--Barz--Chiello--PDC--
------Pirlo---Marchisio----
--Pepe-----------Giak----
--------ADP--------------
----------Matri-----------
He also used 4-2-4 extensively at Siena beforehand. I remember all the discussion how he was going to fit Vidal into that formation, so he dropped a striker in favour of a 4-3-3 before switching mid-match vs Inter to a 3-5-2 and then mostly sticking with that, until our defensive injury crisis in Feb '12 when we had Caceres and Vidal/Bonny in the center back positions, at which point he temporarily reverted to a 4-3-3.
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What an awesome f*cking game it was though... Licht's opener from Pirlo's first assist, ADP's lofted through ball to Matri, Pepe's strike from ADP's lay off, Vidal's Volley and then Marchisio's dink over the keeper from another Pirlo assist... T'was magic!
Pre-Borriellol Matri!

Pre Angelli dogacting Capitano!

Lo Swing di Pepe!

Pirlo!
I know this sounds almost ridiculous but a part of me thinks we played a better brand of our own game last year compared to this year, last season we looked utterly relentless, always pressing, always fast and mobile, out attackers always breaking forward and pressuring the opponents. I fell that this year we lacked that commitment, drive, resolve, urgency and grinta in comparison to the 2011/12 season.