Maverick Vinales knows Monster Energy Yahama must improve despite a winning start to the MotoGP season at the Qatar Grand Prix.

Vinales shot from fifth with 15 laps to go to first with seven rounds of the track remaining in Doha on Sunday, nipping ahead of Francesco Bagnaia, who started on pole.

It ultimately proved a relatively comfortable triumph for the Spaniard, with the drama coming further back – defending champion Joan Mir losing out on a podium place with a mistake at the final corner.

However, after suffering a slow start from which he subsequently struck back, Vinales conceded there is work to do for his team.

"We are not there yet. We need to improve," he said during a news conference.

"We need to work really hard because it's just the first race. We stick with our feet on the ground, and we'll work hard for the next one, to be faster, especially from the start, we have to be better."

Vinales praised the work the team has done in pre-season, though, as well as the impact made by new Yamaha test driver Cal Crutchlow.

"I didn't have that feeling during other weekends to have that corner speed, but with Yamaha we work very hard to have that front part of the bike to make it better," he said.

"Also, Cal works very hard with the bike. The way Cal rides the bike is very similar to me, and it helps me with many things, especially because he came from a big factory and he has given us advice which was good for the race."

Despite demolishing the Losail circuit lap record in qualifying, Ducati debutant Bagnaia looked set to miss out on a place in the top three when Johann Zarco – of his former team Pramac Racing – and Mir overtook him.

However, Mir's slip-up with just one turn left to go allowed Bagnaia to take third place and the Italian conceded he needs to find a balance between starting strong, without giving up a lead.

"Maybe for the next one, I have to change the strategy a bit, push less in the first part of the race and follow someone, but in any case we have more data now to look at," he said.

"We will improve for sure, to be better in the last part of the race."

Maverick Vinales got his 2021 MotoGP campaign up and running with a season-opening victory as he charged up from fifth at the Qatar Grand Prix.

Pole-setter Francesco Bagnaia could not get away from the chasing pack, which included Johann Zarco (Pramac Racing) and his Ducati team-mate Jack Miller.

With defending world champion Joan Mir – starting in 10th – and fellow Suzuki rider Alex Rins struggling to keep pace initially, it was Monster Yamaha's Vinales who made his move.

Finding himself in fifth with 15 laps remaining, Vinales closed the gap on Bagnaia by the time the final seven came around.

After threatening once but being held off, Vinales spotted a gap and dived through to take a lead he would not relinquish.

Bagnaia's race looked set to go from bad to worse when he dropped out of the top three altogether.

It left Zarco and Mir tussling for second, and last year's champion had the edge on the last lap yet, in a remarkable twist, he fell short on the final corner.

Mir appeared to run wide, with his exit speed dropping and allowing Zarco to clinch second – Bagnaia, who had blitzed the Losail lap record in qualifying, battling back to mark his first race for Ducati with a podium finish.

Fabio Quartararo completed the top five, with Mir's team-mate Rins finishing sixth.

There was misery for Takaaki Nakagami, who crashed out on turn nine midway through the race, with Danilo Petrucci's Tech3 KTM debut also coming to a premature end.

Francesco Bagnaia targeted "a really great result" at the Qatar Grand Prix after setting a stunning lap record on his factory Ducati debut.

Third-year MotoGP rider Bagnaia had finished 15th and 16th in his two seasons with Pramac Racing but has quickly focused on loftier ambitions following his bow with the factory team.

Ducati - winners of the previous two Qatar GPs with the since-departed Andrea Dovizioso - had been fast all week at the season opener, with Jack Miller setting the practice pace in his 100th grand prix with a best time of one minute and 53.387 seconds ahead of second-placed team-mate Bagnaia.

But Bagnaia later suggested he had believed he could run in less than 1:53 in qualifying and so it proved, a magnificent 1:52.772 setting a two-wheel lap record at the Losail International Circuit.

That was enough for a healthy 0.266-second gap to Fabio Quartararo, while Bagnaia gave veteran Valentino Rossi - a four-time Qatar winner - a tow to take him to the front of the second row.

Rossi has 10 podiums at Losail and his next in MotoGP will make him the first to 200.

Even from his commanding position, Bagnaia could be forgiven for being pessimistic after his year-high six abandonments in 2020 - including five in the final eight races - but he was full of positivity following an outstanding display.

"I'm very happy," he said. "Already yesterday I was thinking it was possible today to arrive at (1:)52.

"In the second attempt, when I started pushing, I thought it was possible. After the third sector, I was very close to this lap time.

"I'm very happy; my first pole position in my first race with this team. I would like to make everything possible to finish the race tomorrow in the best way possible. I think we can make a really great result."

Miller had to settle for fifth, next to Rossi, as he pursues a third straight podium for the first time in his career following two to end 2020.

Quartararo also had reason to be disappointed with his day as he mistimed his second run and the chequered flag denied him the opportunity to challenge Bagnaia.

Another debutant at a factory team, Yamaha's Quartararo won the first two races of the season last year but has had only one podium in 12 outings since.

The 21-year-old, who has colleague Maverick Vinales - the 2017 Qatar winner - behind him in third, said: "It's a shame I couldn't do the second lap on my second run. I had the chequered flag for a second.

"But I'm quite happy. I think we did a great lap. We tried something in FP4 that was bad, honestly - I didn't feel great on the bike. But I feel that we have great potential for tomorrow.

"We will go with that bike for the race because it's the one that I feel good [on]. I think we made too much changes today, but I'm feeling happy.

"I think we did a great, great job in the qualifying. Now we're just missing the race. I can't wait."

Neither the Ducatis nor the Yamahas should have to worry this weekend about defending champion Joan Mir, who failed to capitalise on the absence of Repsol Honda great Marc Marquez.

Mir was forced to contend in Q1 and will start from 10th, having finished eighth in his only previous Losail entry in 2018.

Provisional classification

1. Francesco Bagnaia (Ducati) 1:52.772
2. Fabio Quartararo (Monster Yamaha) +0.266s
3. Maverick Vinales (Monster Yamaha) +0.316s
4. Valentino Rossi (Petronas Yamaha) +0.342s
5. Jack Miller (Ducati) +0.443s
6. Johann Zarco (Pramac Racing) +0.514s
7. Franco Morbidelli (Petronas Yamaha) +0.541s
8. Aleix Espargaro (Aprilia Racing Team) +0.543s
9. Alex Rins (Team Suzuki Ecstar) +0.718s
10. Joan Mir (Team Suzuki Ecstar) +0.910s
11. Takaaki Nakagami (LCR Honda) +0.949s
12. Pol Espargaro (Repsol Honda) +1.158s