Gimmi Bruni scored Trident Racing's first GP2 win with a dominant performance at Imola.
Bruni led away from pole and was never headed during the 37-lap race. He fended off a stiff challenge from Lewis Hamilton in the early stages before establishing a comfortable lead.
Even the intervention of the safety car failed to knock him off his rhythm and he made a great start to sprint away to victory.
Second looked set to go to Nelson Piquet Jr, but his car was hobbled in the late stages and he was powerless to hold off the impressive Michael Ammermuller.
Nicolas Lapierre also passed Piquet to make it two Arden drivers on the podium, while the erstwhile championship leader suffered further heartache when Alex Premat overtook him for fourth on the final lap.
Ernesto Viso collected sixth, while seventh went to Timo Glock, while Hiro Yoshimoto took the final point and pole position for race two. The Japanese had been in contention for a podium, but was forced to make a second pitstop, which dropped him back.
Hamilton was disqualified after passing the safety car, while Adam Carroll spun out while running sixth.
CLASSIFIED: Pos Driver Team Time 1. Bruni Trident Racing 1h 01:13.889 2. Ammermueller Arden International + 10.907 3. Lapierre Arden International + 14.514 4. Premat ART Grand Prix + 15.713 5. Piquet Jr. Piquet Sports + 16.772 6. Viso iSport International + 19.669 7. Glock BCN Competicion + 47.806 8. Yoshimoto BCN Competicion + 48.208 9. Valles Campos Racing + 52.315 10. Porteiro Campos Racing + 69.547 11. Filippi FMS International + 83.448 12. Monfardini DAMS + 83.703 13. Villa Racing Engineering + 87.070 NOT CLASSIFIED: Driver Team Laps Zuber Trident Racing 30 Gommendy iSport International 30 Fauzy Super Nova International 29 Carroll Racing Engineering 26 Tahinci FMS International 25 Hernandez Durango 25 Negrao Piquet Sports 13 Perera DAMS 13 Di Grassi Durango 7 Pla DPR 7 Lopez Super Nova International 1 Piccione DPR 0 Fastest lap: Valles, 1:35.261 on lap 13