The fast, diminutive Italian international striker Insigne struck clinically on five minutes and was unstoppable when he raced down the left flank to square for the third goal from Hirving Lozano.

Napoli's other striker Andrea Petagna set up Insigne's opener and also crossed for the second goal scored by Diego Demme.

Piotr Zielinski fired in off the left post to effectively wrap up matters by halftime and Insigne then converted a penalty before a late effort from substitute Matteo Politano.

"I am happy because it is important to reach goals with this shirt as a Neapolitan," Insigne said.

"But I am more happy about the win because we played as a team with a great display.

"We made some mistakes in previous games but the good thing is that every three days you have a chance to bounce back."

In Bergamo, Atalanta were held to a 0-0 draw by lowly visitors Genoa, which left them still in sixth.

Elsewhere, Sassuolo salvaged a 1-1 draw against second-to-bottom Parma thanks to a stoppage-time penalty.

Crotone stayed last despite beating Benevento 4-1 with a brace from Nigerian striker Simy.

Benevento had Marco Sau red-carded for his protests after the hosts' fourth goal.

Napoli now have a game in hand and sit six points behind leaders AC Milan, who close matchday 18 at Cagliari on Monday.

Second-placed Inter Milan and fifth-placed champions Juventus were meeting in a potential league classic later on Sunday.

Australian Associated Press