The South African Darryn Binder took his first win in Moto3 in Catalonia on Sunday as two of the main world title contenders, Albert Arenas and John McPhee, both had to abandon.
The 22-year-old Binder, whose older brother Brad rides for KTM in MotoGP, started way back in 20th position on the grid but came through to take the victory ahead of the Italians Tony Arbolino and Dennis Foggia.
"It is an extraordinary feeling. I have waited a long time but today I did everything I could," said Binder, who rides for the CIP Green Power team.
Japanese rider Ai Ogura finished 11th and leads the championship, three points ahead of Arenas.
Moto2 championship leader Luca Marini, on a Kalex, tightened his grip on the title race with a pole to line victory which marked the Italian's third win of the season.
Britain's Sam Lowes finished second with 21-year-old Italian Fabio Di Giannantonio in third for his first podium of the year.
Marini now holds a 20-point lead in the title race ahead of fellow Italian Enea Bastianini, who finished sixth.
The race followed early drama during the warm-up for Augusto Fernandez whose Kalex burst into flames as the Spaniard headed into turn 10. Fortunately, Fernandez escaped injury.