Pato scored twice as the his two goals, plus a late Robinho strike downed a resilient Chievo who fought back well.
Chievo started the match the brighter of the two side with Kevin Constant making his presence felt down the left side, but Milan soon found their feet and drive from midfield as Gennaro Gattuso drove his side forward. However, Milan's forward line were misfiring and not connecting with the many through passes played.
It seemed as if the Chievo defense had the answer to Milan's front line with Zlatan Ibrahimovic and Clarence Seedorf going close with a couple of early crosses but Chievo handled their other foray's forward with relative ease.
But the constant pressure led to a lapse in concentration as Ibrahimovic received the ball from Luca Antonini on the left before playing a lovely dinked cross to the far post where Pato had peeled away from his marker to volley into the far corner to give Milan the lead.
Chievo did have a couple of chances with Constant firing wide from just outside the box, whilst also forcing Abbiati into a magnificent double save and Pablo Granoche heading straight at the Milan keeper.
The second goal for Milan came not long after with Ibrahimovic and Pato combining once more. The Swede took a quick free kick and played Pato through and the Brazilian made no mistake, firing into the back of the net.
For the remainder of the first half Milan operated on the counter attack with Ibrahimovic once more combining with Pato, this time sending the Brazilian through on goal from his own half but Stefano Sorrentino denied the youngster with an excellent save.
The second period opened with Chievo having the better of the game once more as they looked for a way back into the match, but Milan were now always a danger on the counter.
Bostjan Cesar then made the game a lot more interesting as the pace began to slow. Sergio Pellissier flicked over a corner at the near post and the ball deflected in off Cesar to offer the Flying Donkeys hope.
Pellissier then thought he had brought his side level but he was flagged offside and the Rossoneri breathed a collective sigh of relief. But as the half wore on Milan were becoming visibly more frustrated as Chievo pressed them at every opportunity but the home side scored a late goal via Robinho which settled the tie.
After tonight's result Milan move to the top of Serie A , while Chievo remain in fifth position, but both could slide down the table once the full card of fixtures have been played.
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