Napoli continued their 100 percent start to the season and stretched their lead at the top of Serie A to two points with a 3-0 win over Cagliari at the Stadio San Paolo on Sunday.
Marek Hamsik handed the hosts an early lead by scoring his first goal of the campaign with a low, angled shot in the fourth minute.
Top-scorer Dries Mertens then netted his ninth goal in all competitions this season by slotting home from the penalty spot five minutes before the interval.
Kalidou Koulibaly rounded off the win with a close-range finish two minutes into the second period.
Second-placed Juventus had started the day on the same number of points as Napoli but lost their perfect Serie A record when they were held to a 2-2 draw away at Atalanta.
Federico Bernardeschi and Gonzalo Higuain put the champions 2-0 up inside 24 minutes, but Mattia Caldara and Bryan Cristante scored either side of the interval to earn the hosts a point.
Paolo Dybala missed a chance to grab the winner nine minutes from time when Juventus were awarded a penalty - also through the video referee - after an Andrea Petagna handball in the box.
Massimiliano Allegri's side have been joined on 19 points by Inter Milan, who defeated Benevento 2-1 away thanks to a Marcelo Brozovic double.
Juventus retain second place in the table thanks to a superior goal difference.
Lazio will go into the international break in fourth place, five points adrift of Napoli, after beating Sassuolo 6-1 at the Stadio Olimpico.
Luis Alberto and Marco Parolo both scored braces for Simone Inzaghi's side, while Stefan de Vrij and Ciro Immobile completed the rout.
(Hamsik 4, Mertens 40-pen, Koulibaly 47) Cagliari 0
(Paloschi 39) Crotone 1
(Falque 31, Niang 44) Verona 2
(Kean 89, Pazzini 90+2-pen)
(Castro 25, 46) Fiorentina 1
(D'Alessandro 42) Inter 2
(Brozovic 19, 22)
(Alberto 45+1, 57, de Vrij 56, Parolo 64, 69, Immobile 81-pen) Sassuolo 1
AC Milan 0 Roma 2
(Dzeko 72, Florenzi 77)
(Caldara 31, Christante 67) Juventus 2
(Bernardeschi 21, Higuaín 24)