Sacha Fenestraz denied 2015 McLaren Autosport BRDC Award winner Will Palmer the '17 Formula Renault Eurocup title with a second place in the second race at Barcelona.
Palmer, younger brother of former Renault Formula 1 driver Jolyon, needed to win the race with Fenestraz finishing ninth or lower to take the championship fight to the final race of the weekend.
The 20-year-old Briton failed to do so, only finishing sixth after a disappointing qualifying performance restricted him to eighth on the grid, with Fenestraz starting from the front row.
Recent Ferrari Driver Academy signing, and Palmer's R-ace team-mate, Robert Shwartzman was the man on pole, and he held off Fenestraz at the start.
Behind them Gabriel Aubry made contact with Max Defourny through Turn 2, with Defourny, who was runner-up in last season's Eurocup to 2016 MABA winner Lando Norris, spinning backwards into the middle of the track.
With little time to react, 11 cars got caught up in the ensuing mess - several going airborne after launching over the rear of their rivals.
The race was red-flagged for over 20 minutes, and on the restart Josef Kaufmann Racing driver Fenestraz went for the lead again.
He failed to make it past Shwartzman, who used his superior race pace to take his sixth win of the season ahead of the newly crowned champion.
"It just feels amazing," said Fenestraz, who will start the last race of the season from pole.
"To be fair, I think Rob was over the moon this weekend, faster than everybody.
"But we've done the work so, yeah, amazing. So happy. The team did an amazing job all season. I think we deserved this championship, so I can't ask for more than that. I'm over the moon."
Fenestraz, whose brother-in-law is three-time World Touring Car champion Jose Maria Lopez, started the season with two second places, but did not win until the eighth race of the season in Monaco.
He was still very much a title outsider, and did not win again until the Nurburgring in July.
From then on he won at least one race every meeting, including two at the Spa-Francorchamps triple-header, and came to Barcelona with a 52.5-point lead over Palmer and 75 available.
A podium for Palmer in the first race reduced the lead to 46.5, but the Briton's disappointing second race crowned Fenestraz, and means that Shwartzman could end the season as the Franco-Argentinian's closest rival.