AC Milan survived a late scare at Cagliari to restore their three-point lead at the top of Serie A.
Algeria midfielder Ismael Bennacer volleyed in from Olivier Giroud’s lay-off to break the deadlock just before the hour mark.
Leonardo Pavoletti’s 90th-minute header struck the AC Milan crossbar as they held on for a third straight 1-0 win.
Giroud and Brahim Diaz fired wide before half-time, while Franck Kessie’s long-range strike hit a post.
Napoli, who earlier came from behind to win 2-1 at home to Udinese, are second in the table.
Udinese led through Gerard Deulofeu, but Napoli’s Victor Osimhen made it four goals in two games with a rapid double early in the second half.
Udinese’s on-loan Arsenal defender Pablo Mari was shown a red card late on.
Defending champions Inter Milan drew 1-1 at home to Fiorentina to trail rivals Milan by six points, albeit with a game in hand.
Lucas Torreira put Fiorentina in front just after half-time before Denzel Dumfries hit straight back.