AC Milan suffered their fifth defeat of the Serie A season at the hands of visitors Fiorentina on Saturday.
Juan Vargas’ heavily deflected free-kick and Borja Valero’s cool finish helped Fiorentina move into fourth, before Sunday’s matches.
Milan, who were jeered off after the match, are now 10th with 12 points from their 11 games.
Napoli won 2-1 at home against Catania to move within two points of leaders Roma.
Spanish forward Jose Callejon opened scoring for Rafael Benitez’s men with a stunning left-foot curler, before Slovakia midfielder Marek Hamsik doubled the lead with a well-taken first-time shot.
Paul Pogba scored the match winner for defending champions Juventus away at Parma. The Turin-based outfit are level with Napoli- both having won nine of their eleven matches.
Roma, who became the first Serie A side to win their opening 10 matches on Thursday, can restore their five point gap at the top of the standing when they travel to Torino on Sunday.