Milan stalled Scudetto-chasing Napoli thanks to a sensational Gianluigi Donnarumma save on Arkadiusz Milik in stoppages.
The Rossoneri needed points to maintain their European ambitions, but with Leonardo Bonucci suspended and Alessio Romagnoli injured, had to field an all-new centre-back pairing. Jorginho and Raul Albiol returned from their bans after a last-gasp victory over Chievo, but Scudetto-chasing Napoli brought in Christian Maggio to replace suspended Mario Rui, shifting Elseid Hysaj over to the left. It was a strange game for Pepe Reina, who has already agreed a free transfer to Milan for June.
Gianluigi Donnarumma made history as the youngest ever player to reach 100 Serie A appearances, aged just 19 years, one month and 21 days.
The Diavolo had only managed one point in their last six meetings with Napoli, home and away, losing two in a row at San Siro.
Reina immediately had a tough save against his future teammates, getting down to fingertip a Jack Bonaventura daisy-cutter round the base of the near post.
Milan were very aggressive and Nikola Kalinic seemed almost surprised by a Suso cross that hit him on the head to go wide. Napoli took a while to find their rhythm, though after 15 minutes Dries Mertens stung Donnarumma’s gloves.
The initial Rossoneri pressure dissipated and the visitors began to take control, Marek Hamsik and Jose Callejon firing off target, then Lorenzo Insigne slaloming through defenders for a right-foot curler inches wide.
Milan had the ball in the net with Mateo Musacchio, but he was offside when Reina parried the Hakan Calhanoglu screamer into his path.
Straight after the restart, Hamsik tried to square it across rather than go for goal and nobody was ready to take advantage. After a sluggish start to the second half, Maurizio Sarri threw on Arkadiusz Milik and Piotr Zielinski, while Milan replied with Andre Silva.
Insigne controlled a long Zielinski ball over the top, but the angle was too narrow and Donnarumma was able to parry. Kalidou Koulibaly was booked in the final minute and will be suspended against Udinese in the midweek round.
Milik thought he had won it in stoppages when controlling a cross from six yards and firing undisturbed, but Donnarumma somehow managed to fingertip it inches wide.
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