Gianluigi Donnarumma produced a stunning save from Arkadiusz Milik in stoppage time as Milan held Napoli at the San Siro to further damage their opponents’ fading title chances.
Milik seemed certain to score when Lorenzo Insigne’s header found him alone in front of goal but Donnarumma somehow managed to turn his low shot around the foot.
The result leaves Napoli three points behind Juventus, but the defending champions have the chance to widen the gap to six points with a home win over Sampdoria later on Sunday.
Napoli produced their usual slick passing and pinned Milan in their own half for long periods but lacked imagination in the final third, a problem that has arisen as the pressure has mounted in the title race.
Milan, whose faint hopes of finishing in the top four also took a hit, had a goal by defender Mateo Musacchio ruled out for offside in the first half.
Elsewhere in Serie A, bottom side Benevento earned their first away point of the season as Cheick Diabaté notched his third successive double in a 2-2 draw with Sassuolo, while SPAL boosted their survival hopes with a 0-0 draw at Fiorentina and Verona remain in trouble after a 2-0 defeat to Bologna.
Yevhen Konoplyanka and Nando were on target as Schalke beat fierce local rivals Borussia Dortmund 2-0 to close in on a top-four Bundesliga finish.
After failing to make their superiority count in the first half, Schalke took the lead five minutes after the break when Konoplyanka drilled the ball home after a mistake from Marcel Schmelzer.
Brazilian defender Naldo sealed the win for Domenico Tedesco’s team in spectacular style, lashing a long-range free kick into the bottom corner in the 82nd minute.
Schalke are nine points clear of fifth-placed Hoffenheim and four points clear of Leverkusen and Dortmund, who saw in-form loan signing Michy Batshuayi leave the field on a stretcher in stoppage time.