Napoli opened a four-point lead over Juventus in the race for third place in Serie A after Fabian Ruiz's second-half goal helped them win 1-0 at Torino on Saturday.
With two matches left, Napoli are third on 73 points, ahead of fourth-placed Juventus, whose chances of winning the title ended after Friday's 2-1 shock defeat at relegation-threatened Genoa. Torino are 10th on 47 points.
After a dispiriting first half in which Napoli struggled to finish off their chances, central midfielder Ruiz found the breakthrough, firing in a low effort in the 73rd minute.
Ruiz took advantage of Tommaso Pobega's blunder and got past two defenders before finding the net as Luciano Spalletti's side recovered from Lorenzo Insigne missing a penalty on the hour mark.
Torino's best chance to score came in the first half when striker Andrea Belotti attempted a back-flicked header, but Napoli goalkeeper David Ospina dived at full stretch to make a brilliant save.
Later on Saturday, Sassuolo and Udinese drew 1-1, while fifth-placed Lazio beat Sampdoria 2-0 and are now three points ahead of Roma, who have a game in hand, in sixth, with both sides battling to secure a Europa League spot for the next season.
Jose Mourinho's side visit seventh-placed Fiorentina on Monday.
AC Milan will try to regain top spot with a win at Verona on Sunday in their bid for a first Scudetto since 2011.
