Napoli missed the chance to go top of Serie as Antonio Conte's side were held to a goalless draw by struggling Venezia.
The 2023 champions had 15 shots on goal but were frustrated by an excellent performance from home goalkeeper Ionut Radu, whose seven saves earned his second-bottom side a valuable point.
Venezia also had a chance to steal a winner late in added time, but were unable to cap off a sweeping counter-attack with a goal.
Napoli have drawn five of their last seven league games, but Conte said: "I am satisfied with the performance, then we wanted to win it. The positive aspect is that we created a lot, the negative is that we didn't convert them.
"We had to be more incisive, the one who scores goals wins. There are nine games to go, we'll try to be a nuisance until the end, fighting tooth and nail."
Napoli host AC Milan after the international break which Conte said would afford his exhausted squad a break.
"We only have half a team left," he added.
Former Chelsea and Tottenham boss Conte has won Serie A as a manager with Inter and Juventus.
Elsewhere, Bologna thrashed Lazio 5-0 to climb above the Rome side and move into the top four.
Two goals in 94 seconds just after the break were decisive as Riccardo Orsolini and Dan Ndoye put the game beyond Lazio.
Claudio Ranieri's Roma remain in the hunt for a European place as they beat Cagliari 1-0 with Ukraine forward Artem Dovbyk scoring the only goal.
Leaders Inter face third-placed Atalanta later on Sunday night.