Romelu Lukaku ensured Napoli maintained their one-point lead at the top of Serie A with the only goal in Sunday's 1-0 win over his old club Roma.
Belgium striker Lukaku poked home his fifth Napoli goal from Giovanni Di Lorenzo's low cross seven minutes after half-time in Naples, handing veteran Claudio Ranieri a defeat on his return to management with his boyhood club Roma.
Napoli lead Atalanta, Inter Milan, Fiorentina and Lazio by a point -- with Juventus four points off the pace in sixth -- in a crowded title race which is yet to offer up a clear favourite for the Scudetto.
"We knew before kick-off that this was going to be a big match for us because the other teams all won," said Lukaku to Sky Sport.
"It's too early to talk about the title. All we can do is look out for how we develop as a team, work to improve and win every match we play. But now is not the moment to talk about the title."
Napoli were the better team at the Stadio Maradona and should have been ahead as early as the second minute when Khvicha Kvaratskhelia somehow sent a free header wide from less than six yards out.
Kvaratskhelia was also involved four minutes after half-time with a pinpoint cross from which Lukaku glanced just wide.
ROMA 'PROBLEMS', LAZIO HIGHS
Ranieri has a job on his hands at Roma, who are four points above the relegation zone in 12th, but his team were unlucky not to level in the 66th minute when Artem Dovbyk thwacked a header off the bar.
"We have problems, that's why they called me, and we played against a team fighting to win the title," said Ranieri.
"Given all that, I'm happy with the performance. We made mistakes but the desire to get the season on the right track is there."
Roma's struggles will hurt fans all the more given the hot form of their local rivals Lazio, who beat 10-man Bologna 3-0 to claim their seventh straight win in all competitions.
Samuel Gigot nodded home his first Lazio goal 67 minutes into his full Serie A debut and four minutes later captain Mattia Zaccagni curled home a fine finish to effectively end the match as a contest.
Substitute Fisayo Dele-Bashiru completed the scoring in stoppage time for Lazio who sit fifth, some 15 points ahead of Roma as Marco Baroni's side continue to defy expectations.
Bologna, who lost Tommaso Pobega to a red card in the 35th minute, sit eighth on 18 points, but have a game in hand.
REBORN KEAN
Moise Kean continued his revival at Fiorentina by netting in a 2-0 win at Como which was his team's seventh in a row in Serie A.
The 24-year-old has been reborn in Florence after failing to score a single goal at Juventus last season and has scored seven times in his last four matches in Italy's top flight.
"Obviously people look at the goal, but the whole team has worked very hard with him... he's developing and starting to reap the rewards," said Fiorentina coach Raffaele Palladino.
Kean's 68th-minute strike was his ninth in 12 league appearances under Palladino, whose team host champions Inter next weekend.
Fiorentina didn't have things all their own way, and had David de Gea to thank for a superb triple save on the hour mark when they still only led by Yacine Adli's 20th-minute opener.
Como are one point and place above Lecce, who are just inside the relegation zone and take on bottom side Venezia on Monday, after a fifth defeat in a worrying seven-match winless run.
Patrick Vieira was denied a winning start as Genoa manager after a late Roberto Piccoli penalty gave fellow Serie A strugglers Cagliari a 2-2 away draw.
Piccoli's spot-kick leaves Genoa in 16th, level with Cagliari and two points above Lecce.