The draw left Napoli, the only side who can overtake Juventus, six points adrift with two games left. The two sides have the same head-to-head record - which is the next deciding factor after points - but Juventus has a significantly better goal difference.
Napoli president Aurelio De Laurentiis has blamed Sarri.More news: LG K30 with 4G VoLTE launched: Everything you need to know
The fight for the final two Champions League spots from Serie A is heating up and Roma took a significant step toward reaching next season's tournament with a 1-0 win at Cagliari.
Atalanta's 19-year-old Gambian Musa Barrow, the latest player to roll off their production line of young talent, gave them a second-minute lead and Felipe Caicedo scored from close range to equalise midway through the first half.
Inter moved two points behind fourth-placed Lazio who were held 1-1 at home by Atalanta.More news: Google News overhaul to bring more video content, quicker load times
AS Roma, two points ahead of Lazio, strengthened their grip on third place with a 1-0 win at troubled Cagliari thanks to a Cengiz Under goal after 15 minutes.
"We fought at the top right until the end, the title race was decided by certain episodes", Napoli coach Maurizio Sarri said.
Inter put last week's last-gasp 3-2 defeat to Juventus behind them, sealing victory with first-half goals from Andrea Ranocchia, Rafinha and captain Mauro Icardi.
Udinese slip to just a point above the drop zone, with Chievo moving ahead of them after a 2-1 win against relegation rivals Crotone.More news: The Penguins and Capitals are each in unfamiliar territory