Juventus continued to dominate neighbours Torino on Sunday by winning a niggly derby 1-0 with a Paul Pogba goal after resting playmaker Andrea Pirlo.
The Serie A champions completed their ninth match against Torino without conceding a goal, a run stretching back to 2002, and extended their unbeaten run in the fixture to 13.
Inter Milan lost ground on the leaders when they conceded a late goal to draw 1-1 away to homeless Cagliari, Catania beat Chievo 2-0 to clock up their first win of the season and basement club Sassuolo hit back to draw 2-2 with Lazio.
The only goal of the Turin derby came in the 54th minute when Carlos Tevez headed against the crossbar from a corner and Frenchman Pogba reacted quickly to bury the rebound for the visitors, amid suspicions of offside.
Juventus remained unbeaten this season with 16 points from six games, level with Napoli. AS Roma, who began the weekend in top spot with 15 points, were at home to Bologna later on Sunday (1845 GMT). Inter are fourth with 14.
Juventus coach Antonio Conte has made it clear he will rotate the squad this season and, having rested goalkeeper Gianluigi Buffon one week ago, it was 34-year-old Pirlo's turn on Sunday.
The match was predictably intense, with numerous untidy clashes in midfield and few scoring chances.
Inter went ahead when Argentine forward Mauro Icardi nodded in Yuto Nagatomo's cross in the 75th minute only for Radja Nainggolan to equalise for Cagliari with a deflected shot with two minutes left.
Goals from Jaroslav Plasil and Lucas Castro gave Catania their first win of the season and two goals from German Denis propelled Atalanta to a 2-0 win over Udinese.
Andre Dias and Antonio Candreva scored in a four-minute spell early in the second half to put Lazio ahead at Sassuolo. However, Ezequiel Schelotto replied immediately and Antonio Floro Flores equalised in the 76th minute from a free kick.
Sassuolo, making their top flight debut, have still to win a match but have drawn their last two games after starting with four straight defeats.
Promoted Hellas Verona pulled level on 10 points with sixth-placed Lazio, beating Livorno 2-1 with Jorginho scoring the winner with a 74th minute penalty.
