REUTERS: Spaniard Alex Rins celebrated a surprise first MotoGP victory with Suzuki in Texas on Sunday as MotoGP champion Marc Marquez crashed out, ending a six-year winning streak at the Grand Prix of the Americas.
Starting on pole for a seventh year in succession, and chasing his seventh win in a row at the Austin circuit, Marquez lost control of his Honda and slid out on the ninth of 20 laps while leading by nearly four seconds.
The bike would not restart and it was race over for the Spaniard.
Yamaha's Italian great Valentino Rossi inherited the lead but could not hold off Rins, who went past on lap 17 and then held on to win by 0.462 seconds.
Australian Jack Miller finished a distant third for the non-works Pramac Ducati team, with Italian Andrea Dovizioso fourth on a factory Ducati to take the championship lead after three races.
Dovizioso has 54 points with Rossi on 51 and Rins moving up to third on 49. Marquez has 45.
"I beat Valentino, this is unbelievable for me," exclaimed Rins, 23, who had started seventh on the grid. "He was my idol when I was very young."
The victory was Suzuki's first in MotoGP since Spaniard Maverick Vinales won the 2016 British Grand Prix.
Rossi, 40-years-old but closer than ever to his 90th win in the top category, did all he could to retake the lead in the closing laps without finding a way past.
"After Marc crashed, and just when you think it's finished, Rins arrived," said the nine-times world champion across all classes who now has 198 podium finishes in the top class.
"He was a bit faster than me at the end, he rode very well and he beat me.
"It was not a shock because Rins has been very strong from the second half of last year."
Britain's Cal Crutchlow, who was with Marquez and Rossi on the front row, crashed his LCR Honda on the sixth lap when he lost the bike at Turn 11 while in third place.
Rossi's team mate Vinales had to serve a ride-through penalty after stewards ruled he had jumped the start, and finished 11th.
Rins's team mate Joan Mir failed to finish in the points after also being punished for a jumped start.
The big winner of the day was Dovizioso, who had started 13th on the grid and with every expectation of falling further behind Marquez, rather than taking over at the top from his rival.
The next race is the Spanish Grand Prix at Jerez on May 5.
(Writing by Alan Baldwin in London, editing by Christian Radnedge)