Rudi Garcia's men would have dropped beneath the Partenopei with a defeat but Miralem Pjanic's two goals kept the Roman club's excellent 100 per cent record for 2013-14.
The Bosnian midfielder scored a 25-yard free kick as his first goal deep in first-half stoppage-time then doubled his tally with a drilled penalty against the run of play after substitute Paolo Cannavaro was shown a deserved red card to seal the Giallorossi victory and condemn Rafa Benitez to his first defeat as San Paolo coach.
Gonzalo Higuain's fitness concerns saw the Argentine start on the bench, while Roma goalkeeper Morgan De Sanctis featured against his former club for the first time since departing this summer.
Neither goalkeeper were tested in the early stages, as Pepe Reina simply had to stand his ground when Gervinho was through at an acute angle but sliced wide of the left post when under pressure.
Roma were dealt a blow when Francesco Totti was brought off with a thigh injury for Marco Borriello, quieting the Stadio Olimpico crowd somewhat, but supporters were back in full volume in the 35th minute when Daniele De Rossi cleared off the line.
Goran Pandev broke through the gaping Giallorossi defence, saw his shot only semi-saved by De Sanctis but, as the ball was bounced towards goal, the vice-captain chased it down to acrobatically clear.
Lorenzo Insigne looked to have had the final chance of the half but the young Napoli attacker could scarcely believe he struck the post instead of scoring, only realising as he began wheeling away to celebrate.
But Pjanic had the final say in the first half with a perfect free kick that curled into the top left-hand corner after Gervinho was bundled over by a clumsy challenge from Cannavaro, which earned the defender his first yellow card.
Inler clipped the outside of the post as Napoli looked to erase the goal deficit after the break and their attacks were quicker and their tempo more fluent than the Giallorossi's.
In the 58th minute, though, a drilled corner met by the head of De Rossi reminded the visitors of the threat even a blunt Roma can pose, though the Italy international nodded wide.
The game was not end-to-end but the best chances certainly alternated, as Marek Hamsik reacted to De Rossi's miss to make it three woodwork-thumping misses for the visitors.
Though Napoli looked stronger for the 25 minutes after half-time, the tides changed in the 71st minute when Cannavaro was show a second yellow for pulling Borriello to the ground inside the Napoli area.
Pjanic stepped up to lash the spot kick into the top left-hand corner, sending Reina the wrong way and doubling his goal tally for the evening.