Fiorentina ended Inter Milan's perfect record in stunning style while AC Milan were beaten and Lazio moved up to fourth.
Juventus could only draw 1-1 at home to Frosinone in Serie A on Wednesday, as leaders Inter Milan beat Hellas Verona 1-0.
A Gonzalo Higuain-inspired Napoli ran riot against Lazio while there were also wins for Inter Milan and Fiorentina.
Alessandro Cannataro has joined Premier League new boys Bournemouth on a one-year deal, according to Sky sources.
A second-half goal from Fredy Guarin saw Inter Milan edge city rivals AC Milan 1-0 on Sunday evening.
AC Milan's players have been spared another dressing down by coach Sinisa Mihajlovic despite losing to local rivals Inter.
Mario Balotelli hit the post as AC Milan lost 1-0 to leaders Inter in Serie A on Sunday, while Torino remain unbeaten.
Juventus have signed midfielder Anderson Hernanes from Inter Milan for an initial fee of around £8m.
Inter Milan have completed the signing of Ivan Perisic from Wolfsburg on a five-year deal.
Inter Milan have opened talks with Tottenham about signing winger Erik Lamela, according to Sky Italia.
Inter Milan have offered £6m for Liverpool striker Fabio Borini, Sky sources understand.
Serie A champions Juventus saw their 47-match unbeaten home league record come to an end against Udinese.
Everton are interested in signing Inter Milan's captain Andrea Ranocchia, according to Sky sources.
Mateo Kovacic has hailed Real Madrid as the "best club in the world" following his £25m move from Inter Milan.
Stoke City have broken their club transfer record to sign Xherdan Shaqiri from Inter Milan for £12million.
Switzerland international winger Xherdan Shaqiri 'has completed a medical and agreed personal terms with Stoke City'.
Stevan Jovetic has signed for Inter Milan on an 18-month loan deal with a view to a permanent transfer.
Real Madrid continued their fine pre-season form with a 3-0 victory over Inter Milan in the International Champions Cup.
A history of the rivalry between managers Jose Mourinho and Rafael Benitez in their own words...
James Rodriguez scored a glorious free-kick as Real Madrid eased past Inter in the International Champions Cup.