Reigning MotoGP champion Fabio Quartararo put his early-season speed issues behind him as he cruised to victory in the Portuguese Grand Prix on Sunday.

The Yamaha rider dominated the race and finished more than five seconds ahead of fellow Frenchman Johann Zarco of Ducati-Pramac.

Zarco was the beneficiary when Spaniard Joan Mir, on a Suzuki, and Australian Jack Miller, on a Ducati, collided battling for second place in the closing stages.

"I pushed myself to the limit," said Quartararo, who started fifth on the grid.

"I made a great start and I'm happy to win for the first time this season."

Quartararo's first victory since the British Grand Prix last August, lifted him to joint first in the standings, tied on 69 points with Spaniard Alex Rins who started on the eighth row of the grid on his Suzuki.

Spaniard Aleix Espargaro of Aprilia finished third and climbed to third in the standings three points off the leaders.

The next race is the Spanish GP on May 1.