A well-worked goal from Giacomo Raspadori allowed Napoli to beat Stade Brestois, but Antonio Conte had to pull Natan away from a brawl.
The pre-season friendly was played in Castel di Sangro and for the fourth time this summer the Partenopei kept a clean sheet.
Once again, Victor Osimhen was not even on the bench, as negotiations continue to sell him to Chelsea or Paris Saint-Germain.
Leonardo Spinazzola was unlucky not to open the scoring when he fired onto the underside of the crossbar after a corner.
Matteo Politano forced a save before Raspadori’s winner, controlling the cross with his right foot and then firing in with his left.
Kvicha Kvaratskhelia’s curler from the edge of the box thumped the upright and Amir Rrahmani went off with an ice-pack strapped to his left ankle.
Despite only coming on at the 70th minute, defender Natan looked irritable and got into a brawl with Hugo Magnetti, the pair pulled apart by teammates and coach Conte on the touchline.
Napoli 1-0 Stade Brestois
Raspadori 42 (N)
Napoli: Meret (Caprile 70); Di Lorenzo (Mezzoni 89), Rrahmani (Juan Jesus 70), Buongiorno (Natan 70); Mazzocchi (Zerbin 70), Lobotka (Folorunsho 70), Anguissa (Cajuste 70), Spinazzola (Mario Rui 70); Politano (Ngonge 70), Kvaratskhelia (Cheddira 70); Raspadori (Simeone 70)