Juventus power past Atalanta
Carlos Tevez fired Juventus into the lead in the sixth minute but Maxi Moralez's strike saw goalkeeper Gianluigi Buffon's unbeaten streak end at 744 minutes.
Second-half goals from Paul Pogba, Fernando Llorente and Arturo Vidal secured the win.
Second-place Roma remained five points behind after a double from Mehdi Benatia and goals from Mattia Destro and Gervinho.
Fiorentina moved closer to the top three and a Champions League berth as leading Serie A goalscorer Giuseppe Rossi helped it to a hard-fought 1-0 win at Sassuolo.
AC Milan plays city rival Inter later in a highly anticipated derby.
Juventus had won its past eight games, keeping clean sheets in all of them, and it got off to the perfect start when Vidal's pass was deflected into Tevez's path and he beat his defender before firing past Andrea Consigli.
Atalanta leveled when Giacomo Bonaventura forced his way into the right of the penalty area, near the deadball line, and cut back for Maxi Moralez to fire in off the inside of the left upright.
It was the first goal Buffon had conceded in 744 minutes of football. Curiously that matched exactly Roma goalkeeper Morgan De Sanctis' record at the beginning of the season. Both are seventh in the all-time list.
Juventus restored its lead almost immediately after halftime. Llorente touched on Kwadwo Asamoah's cross for Pogba to slide the ball in from close range.
And Llorente sealed the match in the 75th after collecting Giorgio Chiellini's through-ball and beating defender Guilio Migliaccio.
Vidal added a fourth four minutes later, tapping in Stephan Lichtsteiner's cross.
In the capital, Roma captain Francesco Totti - who had made a substitute appearance at AC Milan last week - made his first start after almost two months out with injury.
Roma produced little of note until the 18th minute when Destro nodded on a corner for Benatia to head in from six yards.
Catania gifted Roma a second goal 11 minutes into the second half when goalkeeper Alberto Frison's poor positioning allowed Maicon's cross to bounce over him and straight to Destro for a simple tap-in into an empty net. It was Destro's third goal in as many matches since coming back from several months out with injury.
Benatia extended Roma's lead moments later, heading Adem Ljajic's free kick into the bottom right corner.
Gervinho somehow failed to score in the 75th when Frison parried a Totti effort into his path and the Ivory Coast forward, who was in acres of space with an empty net in front of him, incredibly hit the right upright from 10 yards.
He atoned for his error when he badly mishit Ljajic's low cross but the ball bounced past Frison and into the back of the net.
Roma moved five points ahead of Napoli, which drew at Cagliari on Saturday. Juventus hosts Roma immediately after the winter break.
Fiorentina is three points behind Napoli after Rossi secured a late win eight minutes from time, taking advantage as the ball bounced off a Sassuolo defender before he fired it into the bottom left corner.
The American-born Rossi, who plays for the Italian national team, is the top scorer in Serie A with 14 goals, three more than Tevez.
Josip Ilicic should have sealed the match but he hit the post.
Newly promoted Hellas Verona moved provisionally above Inter, into fifth place, with a 4-1 win over Lazio.
Luca Toni scored twice and also set up a goal for Romulo. Juan Iturbe scored Verona's second goal with a 30-meter free kick into the bottom right corner.
Lucas Biglia had leveled for Lazio, which has won only one of its past eight league matches.
Torino also scored four goals as it came from behind to beat Chievo Verona 4-1.
Cyril Thereau gave Chievo a surprise lead when he rushed in to fire home Gennaro Sardo's cross but a double from Ciro Immobile, either side of the break, put Torino in front.
Giuseppe Vives and Alessio Cerci secured the three points.
Elsewhere, Sampdoria held Parma to a 1-1 draw, while earlier Alessandro Diamanti's powerful strike gave Bologna a 1-0 win over Genoa.