Napoli kept in touch with Serie A leaders Juventus with a 5-1 thumping of bottom club Pescara on Sunday while Inter Milan scraped a 1-0 win over Palermo.
Two goals apiece by Gokhan Inler and Edinson Cavani and another from Marek Hamsik moved Walter Mazzarri's Napoli side within two points of Juve who defeated local rivals Torino 3-0 on Saturday.
"We have to carry on with the same attitude we had in the second half because we played badly at the end of the first half and that angered me," said Cavani.
Inter are four points behind Juve after ending a run of three games without a win.
However their stodgy display will not inspire confidence they can sustain a serious title challenge particularly with playmaker Wesley Sneijder sidelined over a contract dispute.
Lazio are six points off the pace in fourth spot after beating Parma 2-1 thanks to a 25th-minute effort from defender Giuseppe Biava and Miroslav Klose's ninth league goal of the season.
Ishak Belfodil pulled one back for Parma in the 66th minute, converting the rebound after his penalty was saved.
AS Roma are sixth after coming back from a goal down to win 3-1 at lowly Siena.
Two goals from rejuvenated former Siena striker Mattia Destro and one by Simone Perrotta gave Zdenek Zeman's side a deserved victory in a match where they missed a hatful of chances.
A first half hat-trick from Alberto Paloschi and a last minute tap-in by Adrian Stoian gave Chievo a 4-2 victory at fellow strugglers Genoa and their first away points of the season.
Genoa's fourth straight home defeat saw them slip into the bottom three with 12 points, only one ahead of Pescara.
Bologna beat Atalanta 2-1 thanks to a deflected free kick from Alessandro Diamanti in the 16th minute and a second-half goal from former Atalanta player Manolo Gabbiadini while Udinese stayed in mid-table despite a 4-1 rout of Cagliari.
Seria A: Napoli jump to second, Inter lose
Serie A: Milan edge Siena, go one point clear of Juve, Udinese
Roundup: United go top, Juve's unbeaten run ends
AC Milan fight back to beat 10-man Catania
Serie A: Napoli down Milan as Cavani 'tricks'