Arkadiusz Milik scored one and set up the other for Fabian Ruiz, as Napoli pushed past Sassuolo to book a Coppa Italia quarter-final with Milan.
The Partenopei had to do without Dries Mertens, Marek Hamsik, Raul Albiol, Piotr Zielinski and suspended Simone Verdi, while Sassuolo missed Marlon, Gian Marco Ferrari, Federico Di Francesco, Claud Adjapong and Alessandro Matri, but Kevin-Prince Boateng returned from a long lay-off.
Only four Neroverdi fans made the trip down to the Stadio San Paolo, with the overall attendance at around 15,000.
It was a bright start from both sides, as Domenico Berardi failed to make the most of a defensive error and on the counter Jose Callejon fired straight at the goalkeeper one-on-one.
The opening goal came at the end of a long period of Napoli possession, as Gianluca Pegolo flapped at Lorenzo Insigne’s cross and it ricocheted in off the stomach of Arek Milik.
The hosts continued to dominate the ball and Insigne’s snapshot whistled off target, but Sassuolo thought they had drawn level on 35 minutes with Manuel Locatelli. His initial ferocious strike from distance stung David Ospina’s gloves, the Elseid Hysaj clearance was poor and Berardi sent Locatelli back in to finish it off. However, the referee decided after a VAR review that Locatelli handled in the build-up and the goal was disallowed.
Berardi’s curler was just over and in the second half Kalidou Koulibaly needed a crucial tackle to prevent the Alfred Duncan tap-in, Ospina smothering a Stefano Sensi half-volley.
It was an increasingly ill-tempered game with numerous yellow cards. Just as Sassuolo seemed to be pressuring Napoli, the hosts doubled their lead. Milik controlled a long Insigne cross-field pass, pulled back for Fabian Ruiz and the Spaniard put his foot through it into the far bottom corner.
Half the stadium thought Insigne’s free kick had flown in, but it only struck the side-netting. Locatelli should’ve got one back for Sassuolo in the final minute, but he came sliding on to the Pol Lirola assist from six yards and prodded it straight at Ospina.
There was even time for youth team player Gianluca Gaetano to make his senior Napoli debut and created a very good chance, denied by a desperate Magnani challenge.
Napoli 2-0 Sassuolo
Milik 15 (N), Fabian Ruiz 74 (N)
Napoli: Ospina; Hysaj, Maksimovic, Koulibaly, Mario Rui; Callejon (Younes 82), Diawara, Fabian Ruiz, Ounas (Allan 71); Milik (Gaetano 90), Insigne
Sassuolo: Pegolo; Lirola, Magnani, Peluso, Rogerio (Dell’Orco 82); Locatelli, Sensi, Duncan; Berardi, Boateng (Babacar 69), Djuricic (Boga 69)