Juventus' Tevez celebrates with his teammate Isla after scoring against Catania during their Italian Serie A soccer match at the Juventus stadium in Turin (Photo: Reuters)
Jose Maria Callejon and Dries Mertens scored to help Napoli to a 2-1 win at Fiorentina. U.S.-born forward Giuseppe Rossi had leveled from the penalty spot with his ninth goal in 10 games.
Napoli's Christian Maggio and Fiorentina's Juan Cuadrado were sent off in the final 10 minutes.
Juventus beat Catania 4-0 with goals from Arturo Vidal, Andrea Pirlo, Carlos Tevez and Leonardo Bonucci. Catania midfielder Tiberio Guarente was shown a second yellow card six minutes from time.
Napoli and Juventus are two points behind Roma, which has won all nine of its opening matches and hosts rock-bottom Chievo Verona on Thursday.
Fiorentina was looking for a fourth straight win in all competitions but was still without Mario Gomez, Massimo Ambrosini, Mati Fernandez and Josip Ilicic. Napoli decided to rest Marek Hamsik in favor of Goran Pandev.
The home side dominated the early stages but it was Napoli which took the lead when Gonzalo Higuain put in a delightful cross for fellow summer signing Callejon to volley across into the bottom left corner.
Fiorentina was given the chance to level shortly before the half hour when Federico Fernandez was adjudged to have pushed over Stefan Savic in the area. Napoli goalkeeper Pepe Reina had recently become the first person to save a Mario Balotelli penalty but he was unable to prevent Rossi's spot kick from going into the bottom left corner.
Napoli restored its lead nine minutes from halftime. Mertens won the ball and raced into the area before firing into the bottom right corner.
The visitors were forced to play the final 10 minutes with 10 men after Maggio was sent off for a second yellow card.
There was controversy in stoppage time when Cuadrado was shown a second yellow card for diving although it appeared as if he had been tripped in the area by Gokhan Inler.
Catania had managed to draw with Sassuolo at the weekend in Luigi De Canio's first match in charge but had lost all its away games this season.
Juventus took the lead in the 26th minute in somewhat fortunate circumstances as Vidal's effort took a double deflection to wrongfoot Catania goalkeeper Mariano Andujar.
Free-kick specialist Pirlo doubled Juve's advantage nine minutes later, curling in an unstoppable effort from just outside the area.
Claudio Marchisio drove a shot off the post early in the second half before Tevez and Bonucci sealed the result.
Milan was desperate for victory after slipping to 10th following two defeats in its last three matches and Lazio had not won at San Siro since 1989.
Kaka, who had twice gone close in the first half, broke the deadlock nine minutes after the interval, curling a stunning strike into the top right corner for his first Milan goal in four and a half years following an unhappy spell at Real Madrid.
Milan has conceded more headed goals than any other team this season and its defense was again caught napping to allow Michael Ciani to equalise with a free header from Antonio Candreva's cross.
In an incredible match at Livorno, the home side came back from two goals down to lead but drew 3-3 against Torino.
Ciro Immobile and Kamil Glik put Torino 2-0 up with less than eight minutes on the clock but goals from Paulinho and Leandro Greco saw Livorno level at halftime.
The comeback was complete when Emerson lashed an absolute screamer under the crossbar to put Livorno in front but Alessio Cerci's penalty helped Torino snatch a point following Leandro Rinaudo's handball.
Bologna is level on points with Livorno, three points off the drop zone after goals from Gyorgy Garics, Panagiotis Kone and Michele Pazienza helped it to a convincing 3-0 win at Cagliari.
The home side played with 10 men for most of the second half after Nicola Murru was sent off in the 52nd minute for a second booking.
Sampdoria is also level with Bologna and Livorno after it lost 2-0 at high-flying Hellas Verona.
Juanito Gomez Taleb and Luca Toni scored in the second half to help newly-promoted Verona maintain its 100 per cent home record and move into fifth in the standings.
Elsewhere, Udinese won 2-1 at 10-man Sassuolo while Alberto Gilardino had a penalty saved before scoring against his former club to help Genoa beat Parma 1-0.
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