Bagnaia won MotoGP's first-ever sprint on Saturday to move top of the standings and victory in Sunday's race, which he dominated after taking the lead, earned him another 25 points.

Australian Jack Miller, who had finished fourth in the sprint, ended up seventh on his new KTM in what was an encouraging weekend for the Queenslander. 

The day's biggest drama came with Honda's Marc Marquez ending up apologising for a bad mistake and accepting a penalty after he collided with Portuguese hope Miguel Oliveira in an incident that saw both riders crash out.

Italian Bagnaia, Miller's old teammate, celebrated his victory with Portuguese football star Cristiano Ronaldo's trademark goal celebration, much to the home crowd's delight.

Aprilia's Maverick Vinales and VR46 Racing's Marco Bezzecchi completed the podium, but it was Bagnaia who was happiest as he started the season strongly after waiting six races last year for his first win and podium.

Marquez's drama occurred when he was attempting to move up to third and clipped Pramac Racing's Jorge Martin, who managed to maintain his balance, before the Honda rider barged straight into Oliveira.

"First of all, I'm very sorry to Oli, his team, to his fans at the Portuguese GP. I did a big mistake," Marquez told MotoGP afterwards.

"It was not my intention obviously; my intention was not even to overtake Martin at that point. I had a massive lock on the front (tyre), maybe the hard front (tyre) option was not ready.

"After that big lock I released the brakes and when I released the brakes the bike goes inside and I was able to avoid contact with Martin but not with Oli."

The Portuguese crowd looked on in despair as Oliveira missed out on a potential podium on home turf and Marquez also apologised to the fans in the grandstand after he returned to the paddock.

The six-times world champ was also handed a double long lap penalty - if he is fit to ride in the next GP in Argentina.

"I will be penalised in Argentina GP for that mistake, something I completely agree (with). Sometimes these kind of things happen in races and I understand I made a big mistake," he added.

"I have a few injuries but, now, for me it's not important. What's important is Miguel is OK. I will come back when I'm ready."

Vinales capitalised on the incident to move up to second behind leader Bagnaia and Bezzecchi finished third.

But Bagnaia extended his lead over Vinales, who settled his first podium since the San Marino Grand Prix last year while Bezzecchi secured only his second ever MotoGP podium finish.

Johann Zarco sprang a late surprise by picking off riders in the last lap to finish fourth, despite struggling with illness, while Alex Marquez, who made the switch to Gresini Racing this year, finished fifth.

Miller, who started fifth on the grid, stayed in that spot early on but eventually was squeezed back to seventh. 

Over the weekend, he picked up 15 points to lie joint-fourth in the standings, while Bagnaia leads on 37 points, 12 ahead of Vinales.

AAP