Aprilia's Maverick Vinales has claimed the first MotoGP sprint victory of his career at the Portuguese Grand Prix, taking the chequered flag ahead of Marc Marquez and Jorge Martin at the Algarve International Circuit.

Championship leader and reigning world champ Francesco Bagnaia looked well set for a comfortable victory on Saturday when he was in the lead but the Italian went wide with four laps left, allowing the three Spaniards behind him to move ahead.

Marquez had started eighth on the grid but rode his Gresini Racing bike with purpose to claim his first podium on a Ducati machine, overtaking Martin on the final lap with a well-timed lunge to take second on the all-Spanish podium.

"Honestly, I'm happy to be back on the top. We need to concentrate for tomorrow, but we will enjoy today. My first win for Aprilia," said Vinales, who has now won in MotoGP on three different bikes -- Aprilia, Suzuki and Yamaha.

Red Bull KTM's Australian hope Jack Miller had qualified fifth fastest but shot off the line when the lights went out to take the lead on the opening lap.

But the Townsville rider was quickly reeled in by the chasing pack, with Bagnaia moving into lead with 10 laps to go and Miller eventually trailing home fifth.

Marquez was fired up as well after starting eighth on the grid following a crash in qualifying and the six-times champion set the fastest lap, quickly cutting his way through the pack before slotting in behind Bagnaia.

But Vinales, who had overcome a bout of illness on Friday, had qualified second-fastest and the Aprilia rider moved up to sandwich himself in between the two Ducati machines, pushing Marquez down to third.

Marquez lost one more position when sprint king Martin slipped through with seven laps left as the Pramac Racing rider set his sights on Vinales.

But all their eyes lit up when Bagnaia went wide allowing Vinales, Martin and Marquez to move into the top three.

Vinales had free air in front of him and raced into the lead without anyone to challenge him while Marquez waited for the perfect opportunity to pounce on the final lap as he overtook Martin and finished second.

Bagnaia finished fourth, which allowed him to hold on to a slim lead in the championship, two points ahead of last year's title challenger and runner-up Martin.