Oliver Rowland emerged from an enthralling duel with Formula Renault 3.5 title rival Matthieu Vaxiviere to claim his third win of the season at the Hungaroring
Racing Steps-backed Fortec driver Rowland and Lotus F1 junior Vaxiviere occupied their own private battle at the front of the field, finishing almost 20 seconds clear of Strakka Racing's Gustav Malja.
The scrap became most heated on lap 13, when Rowland was forced to defend the inside line into Turns 1 and 2, as Vaxiviere gained an overlap.
Despite a string of fastest laps by Vaxiviere, Rowland eked out a 1.5s margin of victory.
The Briton's win is, however, under investigation.
From fifth on the grid, Rowland made a sensational launch away from the lights; first swerving around the outside of team-mate Jazeman Jaafar and then jinking into the middle of the road to cut between race one winner Egor Orudzhev and pole winner Vaxiviere.
"I made a bad start yesterday, so knew what I had to do to put it right," said Rowland.
"Matthieu had a lot of speed, so I was surprised he could stay so close to me. I was hoping he would drop off!
"I had a long brake pedal with four laps to go to contend with, but this is a fantastic result."
Arden's Orudzhev outbraked himself into Turn 1 and immediately fell out of contention while scrabbling back onto the road from the run-off.
Behind third-placed Malja, there was more action at Turn 2 as Pietro Fantin tapped Roberto Merhi sideways.
Merhi's quick reactions resulted in a save, but the Spaniard dropped behind Fantin and Tom Dillmann to sixth.
Fantin would later receive a 10s penalty for crossing the white line exiting his mandatory pitstop, falling from fifth on the road at the chequered flag to eighth.
Malja's result is the Swede's first podium in his rookie FR3.5 season.
"Like Oliver, I made a good start was able to grab third directly," said Malja.
"I didn't really have the pace to stay with those guys, but starting from sixth this I couldn't really have expected this."
Jazeman Jaafar utilised an early pitstop strategy on lap six, and subsequent rapid lap times, to claim fourth ahead of Carlin's Tom Dillmann.
Along with Rowland, DAMS racer Dean Stoneman is also under investigation after being involved in a minor moment passing Orudzhev at Turn 1 on lap 10.
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