MotoGP's Spanish king of Texas has been dethroned, replaced by his countryman.

Six-time defending race champion Marc Marquez crashed his Repsol Honda halfway through the Grand Prix of the Americas on Sunday, opening the door for Suzuki's Alex Rins to snatch his first career MotoGP victory.

"It was unbelievable," Rins said. "I tried to stay calm on that last lap."

Marquez had been so dominant in six consecutive wins at the Circuit of the Americas that other riders had dubbed him track royalty. And he was well on his way to another easy victory when he went spinning and tumbling through the corner at the end of the long straight.

Marquez was all by himself in the lead when he fell, stunning the field behind him and the crowd that was so used to seeing him dominate the Texas track. He tried to get his motorcycle restarted but gave up when he saw his foot brake was damaged, and then collapsed onto the ground on his back in a dramatic gesture of frustration before he was driven back to his garage.

"Today I did a big mistake," Marquez said. "Sometimes happens. This is racing. It's disappointing ... I was inside my limit. I was riding a very good pace. I was riding very smooth, trying to save the front tire. But we are human. Mistakes are there."

Rins had started on the third row in seventh and was running third behind Yamaha's Valentino Rossi when Marquez crashed. He passed Rossi with four laps to go by cutting under the seven-time former series champion at the track's elevated switchback left turn at the first corner.

"When I was behind Valentino, I was saying, 'C'mon Alex, you need to drive. You need to do a bit of a spectacle,'" Rins said. "When he made a small mistake I overtook him."

Rossi hasn't won since 2017. He stayed close enough for one final move to pass Rins at the same corner where Marquez crashed, but couldn't hold the position.

Rins had won at the track in Moto2 and Moto3 but was winless in his two previous seasons in MotoGP and Suzuki hadn't won at the top level since 2016. He now stands third in the season championship and Rossi considers him a contender for the title.

"When Marc crashed I was surprised. I tried to ride at the maximum. We were fast, (but) at the end Rins was faster," Rossi said. "For sure he is an opponent for the title. He rides very clever he's very smooth with everything."

The fall knocked Marquez from first to fourth in the season championship after three races as he chases his sixth title in seven years. Ducati's Andrea Dovizioso, who finished fourth Sunday and won the season-opening race in Qatar, is the championship leader with Rossi second.

Four riders are now within nine points of the lead as the series heads to its European heartland, starting with the next race in Spain.

"It's been a long time since I win and it was a great opportunity," Rossi said. "(But) these points are important for the championship."