Timothy Castagne and Alejandro Gomez gave the visitors a two-goal advantage and, while Napoli responded through Dries Mertens six minutes from time, they could not find the leveller.

Jose Callejon called Etrit Berisha into action early on with a shot from the left of the box that was saved in the bottom-right corner, before Piotr Zielinski failed to get enough purchase on a close-range effort that was comfortably held by the goalkeeper.

Luigi Sepe then tipped over a Gomez header from the centre of the box, although the effort looked to be sailing off-target anyway, before Castagne struck early in the second half to give Atalanta the lead.

Andreas Cornelius' initial shot was blocked in the box, but the ball fell kindly for the Belgian to fire into the roof of the net.

Appeals for a penalty against Rafael Toloi for handball fell on deaf ears and Atalanta could feel confident of their place in the last four when Gomez sent a left-footed strike into the top-right corner nine minutes from time.

Mertens set up a tense finish when he headed beyond Berisha three minutes later, but Maurizio Sarri's men could not turn it around, leaving Atalanta to take on Juventus or Torino in the semi-finals.