Napoli last won the Serie A title in 1990
Napoli kept alive their slim hopes of winning the Serie A title with a thumping win at Claudio Ranieri's Roma.
Napoli are second, 15 points behind leaders Juventus, who need just 13 points from their last nine games for an eighth straight league title.
Arkadiusz Milik, Dries Mertens, Simone Verdi and Amin Younes all netted for Napoli with Diego Perotti scoring a penalty for the home side.
Ranieri's side stay in sixth place, four points behind AC Milan in fourth.
Roma sacked Eusebio di Francesco on 7 March and won their opening game after appointing Italian veteran Ranieri, but have now suffered back-to-back defeats, having lost 2-1 at SPAL on 16 March.
Roma chairman James Pallotta said after the game: "Everyone knows what has gone wrong this season and that is why we had to make changes but the time for excuses is over.
"The performance against SPAL was not acceptable and today was even worse. These players have to stand up and show they have [guts]. No more alibis for anyone."
