Napoli s Spanish midfielder Fabian Ruiz (R) celebrates after opening the scoring during the Italian Serie A football match between Torino and Napoli on May 7, 2022 at the Olympic stadium in Turin. AFP
Fabian Ruiz scored in the second half after Lorenzo Insigne had another spot kick saved.
Napoli moved four points above fourth-placed Juventus, which lost at Genoa 2-1 on Friday following two late goals from the home side.
It is five points behind league leader Inter Milan, with two matches remaining.
Napoli had a great chance to break the deadlock on the hour mark when Torino defender Armando Izzo tripped Dries Mertens in the area but Insigne's penalty was saved.
It was the fourth time this season that Insigne has failed to convert a penalty.
The visitors did take the lead in the 73rd when Ruiz stole the ball off Tommaso Pobega in the middle of the Torino half and mazed his way into the area before drilling into the bottom left corner.
Lazio was looking to boost its chances of qualifying for Europe when it hosted relegation-threatened Sampdoria later. Sassuolo also played late against Udinese.
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