AC Milan's poor early-season form continued on Sunday when they lost 2-0 at Genoa for their second consecutive defeat.
Giuseppe Sculli struck in the first half and Diego Milito converted a stoppage-time penalty to leave Milan with no points in Serie A after they lost their opener 2-1 to promoted Bologna.
The result increases the pressure on coach Carlo Ancelotti following Milan's disappointing fifth-place finish last season and an embarrassing 2-0 defeat at second-division Swiss side Lugano in a friendly on Wednesday.
Champions Inter Milan beat Catania 2-1 at home and last year's runners-up AS Roma lost 3-1 at Palermo on Saturday. Juventus host Udinese later on Sunday.
Milan, fielding an attacking trio of Ballon d'Or winners Kaka, Andriy Shevchenko and Ronaldinho, made the early running, but Genoa defended well and were dangerous on the counter-attack.
Sculli fired the home side in front on the half hour after Milito had chested the ball into his path.
Milan tried to fashion a response after the break but Genoa continued to pose a threat and keeper Christian Abbiati produced good saves to stop Sculli and Anthony Vanden Borre doubling their side's lead.
Substitute Alexandre Pato blasted Milan's best chance of the second half at Genoa keeper Rubinho.
Argentine Milito wrapped things up with a spot kick after being tripped by Paolo Maldini on his return from Real Zaragoza to the club he played for in 2004 and 2005 in Serie B.
Napoli came from behind to beat Fiorentina 2-1 thanks to second-half goals by Marek Hamsik and Christian Maggio after Adrian Mutu had put the visitors ahead four minutes before the break.
Lazio are the early pacemakers courtesy of a 2-0 home win over Sampdoria secured with goals by Mauro Zarate and Goran Pandev.
Atalanta also have a 100 percent record from two games after Tiberio Guarente gave them a 1-0 victory at Bologna.
The end stands of Napoli's San Paolo stadium were closed and will remain shut for the next two home games as a penalty after violence marred their opening-day visit to Roma.
The game was also one of three games considered high risk which away fans were banned from, along with Genoa-Milan and Saturday's match between Inter and Catania at the San Siro.