Napoli defeated Roma with a fantastic goal from Victor Osimhen to extend their winning streak to 11 games across all competitions.
With 10 minutes remaining, the Nigerian outclassed Chris Smalling for a long ball before dazzling Rui Patricio with a half-volley from a tight angle.
The team led by Luciano Spalletti is three points ahead of AC Milan.
The chances belonged to the visitors, and the video assistant referee reversed a penalty award.
In the first half, Tanguy Ndombele was brought down by Patricio, who should have been awarded a penalty. However, after consulting VAR and viewing the incident once more on the pitchside monitor, the referee changed his mind.
Before the half, the Roma goalkeeper denied Hirving Lozano twice, and Osimhen, making his first start in six weeks, drags a shot just wide.
The top five leagues in Europe still feature only Napoli, Real Madrid, and Paris Saint-Germain as unbeaten teams.
Roma, under Jose Mourinho, who failed to get a shot on goal, are still in fifth place.