Fabio Quartararo won the season-opening Spanish MotoGP in Jerez, a race Britain’s Cal Crutchlow missed after crashing in the warm-up.
Crutchlow, who had qualified sixth, suffered concussion and neck trauma and the 34-year-old LCR Honda rider was later declared unfit to race.
World champion Marc Marquez slid off the track twice in the race, with the second crash forcing his retirement.
Spain’s Maverick Vinales finished second with Andrea Dovizioso third.
Italian Dovizioso had a shoulder operation just two weeks ago.
Quartararo is the first Frenchman to win a premier class race for more than 20 years.
“It’s the most beautiful day of my life,” said the delighted 21-year-old afterwards.
“It felt amazing but strange to realise it because you [usually] have the fans around the track.
“We need to enjoy today a lot because it’s not every day that you have your first MotoGP victory and from tomorrow we will focus on next week’s race.”
The Yamaha satellite rider started from pole but saw his lead taken by Marquez early on before the Spaniard went off into the sand.
Although Marquez recovered to rejoin the field and battle his way up from 14th to third, a heavy crash with four laps to go ended his race and left the Spaniard with a broken arm.
The 27-year-old will now travel to Barcelona for surgery on his right humerus bone.
Once he took the lead, Quartararo controlled matters comfortably, finishing more than four seconds ahead of Vinales.
The MotoGP season had been due to start in Qatar in March but was delayed because of the coronavirus pandemic.
