Napoli missed the chance to cut the gap to Serie A leaders Juventus to just six points, as they were held to a 0-0 draw by a spirited Milan side at San Siro.
In a high-tempo opening period, both sides were guilty of some poor passes in the final third and letting down some impressive build-up play. Hakan Calhanoglu went closest for the hosts with a couple of speculative efforts, whilst Napoli's Jose Callejon drew a good save out of Gianluigi Donnarumma with a fine volley.
The second half started off like the first, but the game's clearest chance saw David Ospina making a fine save from Milan centre-back Matteo Musacchio with less than a quarter of an hour to go.