Ronaldinho produced one of his best performances since joining the club over a year ago to set up the win.

The Brazilian had a goal disallowed and set up both goals for his compatriot Alexandre Pato in the 29th and 48th minutes.

Abdelkader Ghezzal brought Siena level in the 34th minute, but they had to accept defeat to the better team at the Stadio Artemio Franchi.

Earlier, Bologna and Fiorentina shared the spoils in the first Serie A match of the 2009/10 season with a 1-1 draw at the Stadio Dal Ara.

The home side had the better of the first half and took the lead through former Viola striker Pablo Osvaldo in the 24th minute.

Osvaldo missed the chance to make it two before the visitors, boosted by the entry onto the field of Adrian Mutu, equalised through the Romanian striker in the 65th minute to earn a point for Cesare Prandelli's side.