Robinho had given them a controversial first-half lead before Gelson Fernandes equalised in the second period, but Pato came off the bench to score the winner before Bostjan Cesar was dismissed for a second booking late on.

Milan coach Massimiliano Allegri described the victory as a gift to club president Silvio Berlusconi, who was celebrating 25 years as club owner.

"The lads have given president Berlusconi a lovely present," said Allegri.

"I haven't spoken to him yet but he'll surely be pleased, as we all are."

Milan went in front in contentious fashion on 25 minutes.

Antonio Cassano stood the ball up to the back post and Zlatan Ibrahimovic headed it back into the danger zone where Robinho controlled it, spun and trickled a shot into the corner.

However, television replays showed that the Brazilian controlled the ball with his upper arm despite the referee appearing to have a clear and unobstructed view of the incident.

"Robinho's handball was obvious. From the bench I had a perfect view of it and I saw it straight away but even the referee was perfectly placed," complained Chievo coach Stefano Pioli.

Allegri concurred: "From the bench my feeling was that Robinho controlled it with his arm. But at the end of the day, referees' decisions balance themselves out and I don't think there was any bad faith but simply a mistake."

Chievo equalised just after the hour as Frenchman Kevin Constant sent a cross to the back post where Fernandes arrived from deep to head home, with Milan midfielder Alexsander Merkel reacting to his burst just a second too late.

Pato's winner eight minutes from time was a classy strike as he ghosted in between two defenders and shot home off the near post.

The misery continued for Roma as they blew a 3-0 lead to lose 4-3 at Genoa, their fourth defeat in a row.

They seemed to be cruising early in the second half following goals from Philippe Mexes, Nicolas Burdisso and Francesco Totti but they fell victim to the defensive frailty that has blighted their season -- they have conceded 54 goals in 35 matches.

Rodrigo Palacios and substitute Alberto Paloschi both snatched second-half braces to turn the game around and turn up the heat on Roma coach Claudio Ranieri.

Lecce boosted their hopes of escaping relegation while denting Juventus's chances of qualifying for the Champions League with a 2-0 victory.

Djamel Mesbah and Andrea Bertolacci scored for the southerners and Juventus had goalkeeper Gianluigi Buffon sent off.

Hosts Lecce also had captain Giuseppe Vives dismissed in the second half.

After their 1-0 win over champions Inter Milan last week, Juventus returned to earth with a bump, having apparently failed to heed coach Luigi Delneri's warning that this was the more important game.

"We messed up our approach to the game, we were presumptuous," was Delneri's brutal assessment of his troops' performance.

"We deserved to lose. We're not a great team because we don't have the right mentality to play these supposedly easy games."

The turning point came on 12 minutes as David Di Michele chased a ball over the top and reached it before Buffon, who instinctively stuck out a left hand to block his shot, but outside his box, earning him a red card.

Lecce took the lead just past the half-hour mark as Gianni Munari played a perfect ball over the top and Mesbah took it down on his chest before slotting between substitute goalkeeper Marco Storari's legs.

Lecce only had to wait three minutes after the restart for their second as they opened up Juve's creaking defence once again, with Vives chipping the ball to the back post for Di Michele to head across goal, where Bertolacci tapped home.