Siena remain bottom of Serie A with 14 points despite their win but are now only two points behind Palermo and three adrift of Genoa thanks to a 71st-minute header from 35-year-old Albania forward Erjon Bogdani .
Genoa lost 2-0 at home to Catania with Argentine Gonzalo Bergessio scoring after four minutes and his compatriot Pablo Barrientos adding another in the 86th.
Marco Boriello produced an extraordinary miss from six metres and Ciro Immobile twice hit the woodwork for the out-of-sorts hosts, who stayed three points adrift of 17th-placed Pescara.
Pescara also lost at home, 2-0 against Torino, with Mario Santana and Alessio Cerci scoring breakaway goals in the first half.
At the other end of the table Facundo Roncaglia scored a freak goal from his own half as Fiorentina drew 1-1 with Napoli.
And Giampaolo Pazzini's second half brace ensured Milan's return to the top six of Serie A as they beat Bologna 2-1.
