Mario Balotelli scored his first Serie A goal for 1,468 days but Napoli hung on to claim a narrow victory over Brescia at Stadio San Paolo.
Dries Mertens opened the scoring with his fourth league goal of the season before Kostas Manolas headed in the second on the stroke of half-time.
Brescia rallied after the break but Sandro Tonali’s stunning goal was ruled out by VAR for a foul in the build-up.
Balotelli headed home to set up a tense finale, but Napoli held on.
The 29-year-old last found the net in Italy’s top flight on 22 September 2015 in AC Milan’s 3-2 win at Udinese, before spells at Nice and Marseille in France.
He returned to Italy to join hometown club Brescia in August on a three-year deal.
The result sees Napoli strengthen their grip on fourth place in Serie A, while Brescia remain 14th.
Carlo Ancelotti’s side resume their Champions League campaign at Genk on Wednesday, 2 October (17:55 BST), before Brescia face Sassuolo in Serie A on 4 October (19:45).
Elsewhere in the Italian top flight, Edin Dzeko scored a second-half winner as Roma won 1-0 at Lecce to move a point behind Napoli in fifth.
Goals from Sergej Milinkovic-Savic, Stefan Radu, Felipe Caicedo and Ciro Immobile saw Lazio cruise past Genoa 4-0 in the capital to go sixth.
Watford striker Stefano Okaka scored the winner as loan club Udinese beat Bologna 1-0, before the visitors’ disappointing afternoon was compounded when Roberto Soriano was sent off in injury time.
And Davide Faraoni’s equaliser cancelled out Joao Pedro’s opener as Verona drew 1-1 at Cagliari.