David Neres stroked home the only goal of a feisty game in the 36th minute at the Stadio Olimpico, as Napoli beat Roma 1-0.
Roma are surprise leaders of Serie A heading into Sunday's clash with Napoli, a fixture which will go some way to showing whether Gian Piero Gasperini's side are the real deal.
AC Milan also had Mike Maignan to thank for the three points as the France goalkeeper kept out Hakan Calhanoglu's penalty in the 74th minute.
Inter Milan were handed a 2-1 win at Verona by a late own goal on Sunday to move to within a point of stuttering Serie A leaders Napoli.
Paulo Dybala scored his first Serie A goal of the season to give Roma a 1-0 victory at Sassuolo on Sunday to lift them level with leaders Napoli.
Inter Milan moved top of Serie A on goal difference on Saturday after winning 1-0 at Roma, taking advantage of Napoli's shock 1-0 defeat at Torino.
Roma moved top of Serie A on Sunday after coming from behind to win 2-1 at Fiorentina, throwing down the gauntlet to Napoli and AC Milan.
Roma were allowed to have three separate attempts at the same penalty, but were sensationally denied by Lille goalkeeper Berke Ozer in their Europa League clash.
Gian Piero Gasperini has chosen Roma over Juventus who tried to convince him to move to Turin.
Gian Piero Gasperini is set to join Roma on a three-year contract with a net salary of five million euros a season as the capital club try to re-establish themselves in the Serie A top four.
Atalanta qualified for the Champions League on Monday by beating Roma 2-1 and mathematically securing a place in Serie A's top four.
Inter Milan's defence of their Serie A title was hit with a setback on Sunday as they lost 1-0 at home to Roma
Pope Francis died at his home in the Vatican on Monday aged 88 after suffering a stroke.
Roma are seventh, two points behind sixth-placed Lazio with seven matches remaining in the season.
Juventus missed the chance to move into Serie A's Champions League positions on Sunday after being held to a 1-1 draw at fellow top four hopefuls Roma.
Former Premier League duo Dusan Tadic and Edin Dzeko scored in the first half for Fenerbahce.
Joao Felix helped AC Milan into the Italian Cup semi-finals with his first goal for the seven-time European champions in Wednesday's 3-1 win over Roma
Spanish clubs do not tend to splash their cash in the winter transfer windows and this season's was even quieter than usual.