Arkadiusz Milik and Hirving Lozano both scored headers as Napoli followed their Italian Cup triumph with a 2-0 win at Hellas Verona in their return to Serie A on Tuesday.
Napoli beat Juventus on penalties in the Italian Cup final last week after eliminating Inter Milan in the semi-finals, but this was their first league match since beating Torino on February 29 before the coronavirus lockdown.
Almost four months later, they extended their Serie A winning streak to four games against one of their rivals for a European place, while keeping their slim hopes of Champions League qualification alive by moving to within nine points of fourth-placed Atalanta.
Gennaro Gattuso's side remain sixth, three points behind fifth-placed Roma, who play Sampdoria on Wednesday, and four points ahead of ninth-placed Verona.
"We will not relax, we have to create an identity and fight for goals like the Champions League," said Gattuso, as last year's Serie A runners-up face struggling SPAL on Sunday.
"We must continue on this path, believe that work gives us important things, as happened in the Cup.
"I don't know if these 11 games will be enough for us to get into the Champions League, we must already think about the challenge against SPAL."
Polish forward Milik opened the scoring on 36 minutes, nodding in Matteo Politano's corner.
Davide Faraoni thought he had equalised for the hosts after an hour, but his goal was ruled out for a Mattia Zaccagni handball in the build-up.
Lorenzo Insigne missed a chance for a second for the visitors with 10 minutes remaining by curling a shot over.
But Mexican international Lozano, on as an 84th-minute substitute, rose high to head home a Faouzi Ghoulam cross six minutes later.
Napoli goalkeeper David Ospina denied Samuel Di Carmine and Miguel Veloso as Verona suffered their first defeat since the league returned to action.
- Cornelius hat-trick -
Insigne credited Gattuso for turning around the team's fortunes since he took over from the sacked Carlo Ancelotti last December.
"The coach has given us the right determination," said Insigne.
"It can also be seen in the fact that two players who haven't played for a long time, like Ghoulam and Lozano, they came on and were ready.
"His (Gattuso's) imprint can be seen and can help us grow further."
In Genoa, Andreas Cornelius scored his second hat-trick of the season as Parma moved seventh with a 4-1 win over the port city side.
Cornelius also teed up Dejan Kulusevski to add a fourth three minutes from time.
Iago Falque pulled a goal back for Genoa from the spot after Parma goalkeeper Luigi Sepe had earlier stopped Domenico Criscito's penalty.
Parma are level on points with AC Milan and three points off Napoli, with Genoa just above the relegation zone.
Cagliari, meanwhile, earned their first league win since December 2 with Giovanni Simeone scoring three minutes into injury time for a 1-0 win over SPAL.
The Sardinian side move up to 10th place with SPAL second from bottom and facing relegation to Serie B next season.
Torino beat direct relegation rivals Udinese 1-0 for their first win since January 12, moving six points clear of the drop zone.
Torino captain Andrea Belotti rifled in from an angle after quarter of an hour for his 10th league goal this season.
Napoli forward Arkadiusz Milik scored against Verona
Gennaro Gattuso (C with Italian Cup trophy) took over from Carlo Ancelotti as Napoli coach in December.