Juventus moved six points clear at the top of Serie A after Napoli were held to a 0-0 draw by AC Milan at San Siro on Sunday.
Maurizio Sarri’s side controlled much of Sunday’s encounter, but could not find a way to score, with Gianluigi Donnarumma pulling off an incredible save to deny Arkadiusz Milik in stoppage time.
They would also have themselves to blame Lorenzo Insigne and Marek Hamsik passed up decent opportunities either side of the interval, while the offside flag had denied Mateo Musacchio a goal for Milan late in the first half.
Substitute Milik looked set to win this game late on, but he failed to beat Donnarumma from point-blank range.
Milan’s determined display gave them a platform to hit Napoli on the counter, and only terrific defending from Raul Albiol prevented Nikola Kalinic putting Gennaro Gattuso’s side ahead midway through the second period.
A third draw in five league games moves Napoli on to 78 points — six shy of Juventus who won 3-0 over Sampdoria later on Sunday.
Douglas Costa, a 43rd-minute substitute, assisted all three goals.
Mario Mandzukic slammed home Costa’s cross at the end of the first half and Benedikt Howedes headed in his first Juve goal from another centre, and the Brazilian also found Sami Khedira to guide home a third goal.
Juve, who have dropped only four points in the Italian top flight since 19 November, would host Napoli for what potentially could be a title-deciding game next Sunday.