Alexandre Pato sounded a warning to Zlatan Ibrahimovic that he does not intend to give up his place at AC Milan without a fight by scoring twice during an impressive opening-weekend 4-0 win over Lecce.
With Ibrahimovic joining the Rossoneri from Barcelona on an initial loan deal which will become permanent next summer, the pressure was on the young Brazilian and Pato responded with two goals inside the opening 29 minutes as Massimiliano Allegri's first game in charge ended in a comprehensive victory.
Thiago Silva also scored in between Pato's strikes as newly-promoted Lecce endured a tricky return to the top flight. Veteran striker Filippo Inzaghi grabbed a late fourth to complete the win and send Milan - albeit after just one game - to the top of the table.
Bari shocked Juventus with a 1-0 win at the Stadio San Nicola. A stunning goal from Massimo Donati just before the interval was enough to decide the game in Bari's favour and see the Bianconeri, who came into the season with high hopes and expectations, suffer their first setback.
The hosts deserved their win for the courage and conviction they showed in front of almost 50,000 fans.
Sampdoria claimed their first win at the Luigi Ferraris stadium since 1997 by beating Lazio 2-0.
Samp striker Antonio Cassano opened the scoring from the penalty spot on the hour mark after Stephan Lichtsteiner had brought down Daniele Dessena inside the area.
Cassano coolly struck towards the left corner and Lazio goalkeeper Fernando Muslera was unable to get a hand to the effort. The hosts doubled their lead 11 minutes later with a splendid Stefano Guberti lob.
The honours were shared at the Stadio Artemio Franchi in an eventful game which saw both Fiorentina and Napoli end the match with ten men as they started their season with a 1-1 draw.
Edison Cavani gave the hosts an early lead with a disputed goal with Gaetano D'Agostino levelling with a fine strike shortly after half-time before Fiorentina winger Juan Manuel Vargas and Napoli midfielder Manuele Blasi were both sent off in separate incidents.
Brescia endured a disappointing return to Serie A as Parma started the new season with an impressive 2-0 win at the Ennio Tardini stadium.
First half goals from Valeri Bojinov and Stefano Morrone ensured the Gialloblu kicked off the 2010-11 campaign on the right foot.
Sergio Pellissier converted an 84th-minute winner as Chievo got their season off to a perfect start with a 2-1 win at the expense of Catania.
Belgian striker Davide Moscardelli put the home side in front after quarter of an hour but Catania's Adrian Ricchiuti drew the scores level inside seven minutes. That looked to be the end of the scoring until Pellissier won and converted the late spot-kick.
Palermo and Cagliari earned a point each in an entertaining 0-0 draw at the Stadio Renzo Barbera.