Napoli fell to a surprise defeat in Bergamo thanks to a scorching Carlos Carmona volley, losing second place to Inter.
Cagliari secured a fourth consecutive victory in a highly entertaining match with six goals, a red card and two saved penalties.
Chievo were celebrating after seeing off 10-man Pescara, but there was genuine danger for the players when a freak gust of wind propelled metal advertising boards on to the pitch.
Fiorentina finally earned their first away win of the season - their first at Marassi in 30 years - thanks to Manuel Pasqual’s delightful lob, as Gigi Del Neri makes it two defeats out of two at Genoa.
Inter fought back from a goal down to defeat 10-man Sampdoria in a 3-2 Halloween thriller and leapfrogged Napoli into second place.
Bologna made life very difficult for Juventus, but Paul Pogba popped up with the last-gasp winner.
Lazio scraped a 1-1 home draw against Torino under the driving rain, but the Granata wasted golden opportunities.
Palermo had dominated the first hour and were 2-0 up, but Stephan El Shaarawy completed a Milan comeback to snatch a Coach-saving draw in Sicily.
Roma fell into another nightmare, dropping their lead for a 3-2 defeat to Parma at the rain-soaked Stadio Tardini.
It was a Halloween thriller at the Friuli, as Udinese were in front, fell behind and Antonio Di Natale grabbed a heart-stopping equaliser.