Mertens and Maradona are tied for third on the club list of Serie A scorers behind 1930s star Antonio Vojak.
Rome: Dries Mertens matched Diego Maradona with his 81st Serie A goal for Napoli and Carlo Ancelotti's squad bounced back from a run of poor results for a 2-0 win at relegation-threatened Frosinone on Sunday.
Mertens scored the opener with a perfectly executed free kick around Frosinone's wall into the near top corner.
Mertens and Maradona are tied for third on the club list of Serie A scorers behind 1930s star Antonio Vojak (102 goals) and recently departed captain Marek Hamsik (100).
Amin Younes doubled the lead after the break, dribbling by two defenders before sending an angled shot into the far corner.
Napoli also hit the woodwork twice in only its second league win of its last five matches. The southern club was also recently eliminated from the Europa League quarterfinals by Arsenal.
Napoli is firmly second, 18 points behind Italian champion Juventus and eight ahead of third place Inter Milan with four rounds remaining.
Frosinone is in penultimate position.