Milan: Kevin-Prince Boateng scored a hat-trick within 18 minutes of coming on as a halftime substitute as AC Milan bounced back from being 3-0 behind to win 4-3 at Lecce in an astonishing Serie A match.
Mario Yepes` 82nd minute header completed the fightback for the defending champions who trailed to goals from Uruguayans Guillermo Giacomazzi and Carlos Grossmuller and a Massimo Oddo penalty after a shambolic first-half display.
Antonio Di Natale, league top scorer last season, scored twice to give Udinese a 3-0 win over Novara which took them top and Argentine Erik Lamela, 19, scored seven minutes into his Serie A debut in AS Roma`s 1-0 win over Palermo.
Inter Milan won for the only the second time in seven Serie A outings this season when a Thiago Motta header gave them a far from convincing 1-0 win over Chievo.
Udinese, unbeaten after seven games, lead with 15 points while Juventus, who are also unbeaten after being held 2-2 by Genoa on Saturday, have 13.
Cagliari are one point behind after a goalless draw at home to Napoli.
Napoli, Roma and Milan are level on 11 points, as are Lazio who visit Bologna in the evening match.
"I`m happy because Milan are finally where we deserve to be," Boateng, whose side started the weekend a modest 13th, told reporters.
"This isn`t a reply to my critics because I look to the future and not to the past."
Milan coach Massimiliano Allegri added: "A comeback win like this is very important. We got ourselves into a bit of a mess and we did little in the first half, we were too slow, although I had faith we could fight back. I`m happy for Boateng."
Giacomazzi headed Lecce in front after four minutes and former Milan defender Oddo converted a harshly-awarded penalty on the half hour following a foul by Christian Abbiati on Daniele Corvia.
On a bumpy pitch, a mistake by Mark van Bommel set up another Lecce counter-attack seven minutes later which Grossmuller finished off by slotting the ball past Abbiati.
The game changed completely when the ineffective Robinho was replaced by the heavily-tattooed Boateng at halftime.
The Ghana international fired in from close range within four minutes and scored with an exquisite first-time strike from 25 metres following Antonio Cassano`s pass six minutes later.
He levelled with an opportunist goal in the 63rd minute when a rebound from Ignazio Abate`s shot landed at his feet, although Yepes was clearly offside at time.
Antonio Nocerino hit the bar and Zlatan Ibrahimovic just failed to turn in a Cassano pass for Milan before Cassano`s delicate cross was headed in by Yepes with eight minutes left.
Inter dominated the first half against Chievo at the San Siro with midfielder Wesley Sneijder looking his old self and went ahead when Thiago Motta rose above the defence to score with a powerful header in the 34th minute.
Maicon hit the post for Inter in the second half but they were never entirely comfortable and Bostjan Cesar nearly equalised with a header which Julio Cesar grabbed just under the crossbar.
Claudio Ranieri`s side have seven points in 16th.