Juventus knocks off Inter Milan
Stephan Lichtsteiner, Giorgio Chiellini and Arturo Vidal scored for Juventus before Rolando grabbed a consolation for Inter in the match known as the derby d'Italia - Italy's derby.
Antonio Conte's team extended its lead over second-place Roma, which saw its match against Parma abandoned after eight minutes due to a waterlogged pitch.
Juventus also moved 15 points ahead of Napoli, which fell to a surprise 3-0 loss at Atalanta as German Denis struck twice against his former club.
''We had three or four good counterattacks and then we made a mistake,'' Napoli coach Rafa Benitez said. ''Then we had another chance but then we again made a mistake, and then there was another mistake. In summary, we gifted them three goals.
''Teams put a lot of men behind the ball against us so it's difficult to find space, but when we have chances we have to score. It wasn't my team selection which made the difference today, but mistakes.''
At the other end of the table, Catania drew 3-3 at home to Livorno in a tense relegation battle between the two bottom clubs in Serie A.
Sassuolo also remained in the relegation zone after a 2-1 defeat at home to Hellas Verona, which snapped a run of three successive defeats.
Lazio continued its resurgence under Edy Reja as it comfortably beat Chievo Verona 2-0.
Juventus almost took the lead with less than three minutes on the clock but Inter goalkeeper Samir Handanovic pulled off a fantastic double save to deny Carlos Tevez from point-blank range.
The home side did go in front in the 16th minute when Lichtsteiner was left unmarked to send a diving header into the bottom left corner following a great ball from Andrea Pirlo.
Inter should have reduced the deficit shortly before halftime with its first real chance of the night but Rodrigo Palacio fired narrowly over the bar.
Juventus doubled its lead two minutes after the break when Chiellini - who was wearing the captain's armband in place of the suspended Gianluigi Buffon - capitalized on Paul Pogba's persistence to bundle the ball into the back of the net.
Vidal sealed the match eight minutes later, slotting home the rebound after Handanovic had saved Pogba's effort.
Roland fired into the far bottom corner, through a crowd of bodies to reduce the deficit in the 71st.
Mirko Vucinic came off the bench for Juventus four minutes from time and he almost scored against the club he nearly joined, but saw his effort deflected off the left upright.
Napoli instigated its own downfall in Bergamo as a series of defensive howlers led to a crushing defeat.
Atalanta broke the deadlock less than two minutes after halftime. Blerim Dzemaili gave the ball away in midfield and Denis' powerful drive from outside the area bounced under the diving Napoli goalkeeper Pepe Reina.
Denis - who spent four years at Napoli - doubled his tally in the 65th minute when he latched on to a poor attempted clearance from Gokhan Inler and fired across into the bottom left corner.
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Maxi Moralez sealed the result five minutes later following another error from Federico Fernandez.
Roma's match against Parma was abandoned after only eight minutes' play, with the score at 0-0.
Bottom club Catania remained two points behind Livorno after an entertaining draw, which helps neither club in the relegation battle.
Catania fought back from a goal down three times as Innocent Emeghara scored twice for Livorno, which also had a penalty converted by Paulinho.
Gonzalo Bergessio and Pablo Barrientos scored for Catania, and the home side leveled for the third time in the final minute when substitute Sergio Almiron was left unmarked at the far post to control and fire in a cross.
Livorno moved level on points with Sassuolo after new coach Alberto Malesani's debut ended in defeat against his former club.
Verona broke the deadlock five minutes into the second half when Tomas Manfredini turned Emil Hallfredsson's cross into his own net at full stretch as he attempted to prevent the ball reaching Luca Toni.
Toni all but sealed the match three minutes from time when he beat the offside trap and chipped the onrushing goalkeeper Gianluca Pegolo.
Antonio Floro Flores headed home Domenico Berardi's free kick in stoppage time for a consolation goal for Sassuolo.
Lazio has not lost since Reja replaced Vladimir Petkovic.
It took six minutes for the capital side to take the lead against lowly Chievo as Antonio Candreva fired in Keita Balde's cross.
The 18-year-old Balde capped an impressive performance by scoring Lazio's second, when his effort was deflected into the near corner.