Neel Jani has added a second race win to his GP2 Series resume, but had to fend title contender Nico Rosberg off in the closing stages to ensure that he took all six points.
The Swiss driver led from start to finish, having jumped pole man Ferdinando Monfardini when the race was started behind the safety car after a lights failure, and benefited as the Italian bottled up the drivers behind him.
Giorgio Pantano held third for much of the race, but had no answer to the charging Rosberg, who had already made up places from his seventh spot on the grid, and only followed the German past Monfardini with a handful of laps to run. Rosberg then closed the gap to Jani, who was struggling with a locking left front at Ascari, but was not quite close enough to make his extra pace count before the chequer came out.
Pantano claimed the final podium spot, while Monfardini slipped back into the clutches of points leader Heikki Kovalainen, just holding the Finn at bay as they crossed the line for the final time. Kovalainen simply could not live with title rival Rosberg, at one point slipping back to ninth before clawing his way back into the points. The two championship leaders then vied for the fastest lap bonus, before Scott Speed used a late pit-stop to prepare himself for a smash-and-grab.
Adam Carroll took the final point in an incident-strewn race, despite losing part of his exhaust in the closing stages, the legacy of a narrow escape when Nicolas Lapierre lost control under braking at the Roggia chicane on lap two.
The race got off to an unusual start when the drivers were waiting for the lights to go out and were greeted instead with flashing red lights. The official starting procedure could not be rectified, and instead the pack circulated once more and then took a rolling start. Polesitter Monfardini, however, was unable to hold back fellow front row starter Jani, and the Swiss driver was through well before the first chicane. Even though he carried a touch too much speed to make the corner correctly, the Racing Engineering driver emerged in front, while Monfardini found his mirrors filled by the Super Nova machines of Pantano and Carroll.
Behind the leaders, Rosberg was pushing Nelson Piquet Jr hard for sixth place, powering past the Brazilian into the Parabolica on the first lap, and then getting by Nicolas Lapierre just two corners later. Meanwhile, fellow championship contender Kovalainen was having a torrid time trying to keep up, while Lapierre was also being harried by Piquet. The Frenchman went side-by-side with his Brazilian rival into the second chicane, but went flying through the gravel after appearing to miss his braking point, shooting past Rosberg and almost collecting Carroll on the way.
Kovalainen ran by his shaken team-mate on lap four, but seemed to be struggling for pace and handling on his Arden car. Two laps later, however, the Finn was back down to ninth position after a small mistake, all of his early hard work undone.
Piquet was also struggling, and had dropped into a battle with Hiroki Yoshimoto, the BCN driver determined to bring home some points after his disappointment in Turkey. Yoshimoto looked to have the better of the Brazilian, but the two made contact at the second chicane, putting Piquet out of the race and the Japanese driver into the pits.