Stoffel Vandoorne claimed his third-straight GP2 feature race win of the season at Monaco, after an eventful race in the principality.
Vandoorne finished a comfortable 6.2 seconds ahead of polesitter Alexander Rossi after leapfrogging the American in the pitlane and making his super-soft tyres lap half the race distance.
Ferrari junior Raffaele Marciello, who started on the option tyre, moved into the lead around the outside of Rossi at turn one but was soon under pressure from the fast approaching Rossi and Vandoorne.
Marciello pitted on lap nine, which allowed Rossi and Vandoorne to build a big gap to the chasing pack.
After Mitch Evans collided with Nick Yelloly following an optimistic lunge up the inside, the virtual safety car was deployed.
Rossi and Vandoorne capitalised on the safety car and chose to pit. Fortunately for Vandoorne he was able to jump his rival in the pitlane and was able to extend the gap thereafter.
Julian Leal was able to fight off advances from Sergio Canamasas and Arthur Pic to come home third, however the Columbian received a 10-second penalty for an unsafe release in the pits that resulted in a collision with Sergey Sirotkin.
This promoted Canamasas to the final step on the podium, his second in his GP2 career.
Pic, who couldn’t find a way past the struggling Canamasas, finished fourth ahead of Sirotkin, Leal and Richie Stanaway.
Marciello finished eighth to secure pole for the sprint race, ahead of Jordan King and Yelloly.
The race start itself was delayed after much confusion caused two aborted starts
Nobuharu Matsushita stalled on the grid, causing several others to stall as they tried to squeeze past the stricken ART.
Drivers were allowed to reform in their original positions on the grid for the restart, apart from Pierre Gasly who was deemed to have jumped the start and therefore had to start from the pitlane.
Aside from Evans the only other on track incidents involved Matsushita and Marco Sorensen.
Matsuhita lost out when trying a similar move to Evans on Daniel de Jong at the chicane – losing his front wing in the process.
While Sorensen was left nose first into the Loews hairpin armco after Norman Nato made a lunge which punted the Dane off.