Carlos Sainz Jr took a dominant victory in the first Formula Renault 3.5 race of the weekend at Spa
The Spaniard made a clean getaway to nullify any first lap threat from Red Bull stablemate Pierre Gasly at the start, but behind the lead two things got very messy at Les Combes on the opening lap.
The chasing pack had been mixed up as second row starters Sergey Sirotkin and Richie Stanaway were slow off the line, getting jumped by several cars.
Stanaway then collided with Roberto Merhi as they fought over fifth place turning into Les Combes, and their contact collected Sirotkin and Zoel Amberg, sending the Russian into the tyre wall.
Title contender Oliver Rowland also lost out in the melee, as he was forced to stop to avoid joining the accident.
The Briton tried to fight his way back into the points, but he only got as far as 12th before slowing and pulling into the pits to retire with a fuel-feed problem.
Sainz controlled the restart from the inevitable safety car period and set about building a huge lead, while Gasly - battling brake problems caused by an aborted start - struggled to shake off the chasing pack, led by Matias Laine, Pietro Fantin and Norman Nato.
Fantin's race did not last long after the restart as he was swallowed up by the pack and then turned into the barriers at Les Combes by Meindert van Buuren.
Monaco winner Nato was unable to attack Laine for third, and he eventually lost out to Jazeman Jaafar in the closing stages.
Jaafar appeared to have no answer for Laine - who was running more wing than the Malaysian so was faster in the long middle sector - but on the final lap he got close enough to steal the last podium spot on the run to Les Combes.
Laine came home fourth after running in the top three at the end of every lap except the one that counted, while Nato completed the top five.
Luca Ghiotto earned sixth with a bold pass on Marco Sorensen at Eau Rouge two laps from the end, and Will Stevens was also able to capitalise on the Dane's lost momentum to take seventh.
Results - 18 laps:Pos Driver Team Time/Gap 1. Carlos Sainz Jr DAMS 40m00.447s 2. Pierre Gasly Arden +17.030s 3. Jazeman Jaafar ISR +17.916s 4. Matias Laine Strakka +18.861s 5. Norman Nato DAMS +19.472s 6. Luca Ghiotto Draco +27.725s 7. Will Stevens Strakka +28.316s 8. Marco Sorensen Tech 1 +31.380s 9. Marlon Stockinger Lotus +31.819s 10. Beitske Visser AVF +42.354s 11. Will Buller Arden +45.935s 12. Meindert van Buuren Pons +47.787s 13. Roman Mavlanov Zeta +54.189s Retirements: Oliver Rowland Fortec 10 laps Oscar Tunjo Pons 5 laps Pietro Fantin Draco 4 laps Roberto Merhi Zeta 0 laps Zoel Amberg AVF 0 laps Sergey Sirotkin Fortec 0 laps Richie Stanaway Lotus 0 laps
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