Fabio Quartararo was left baffled as to why his leather race suit split open as he slipped from pole position to a fourth-place finish at the Catalan Grand Prix.

MotoGP championship leader Quartararo was aiming to seal back-to-back wins in Barcelona following his triumph on the circuit in 2020, but the Monster Energy Yahama driver slipped up early on and failed to finish on the podium.

Miguel Oliveira got Red Bull KTM's first win of the season, and the third race victory of his career, with Johann Zarco and Jack Miller completing the top three.

Quartararo was second until the final three laps, when Zarco made a daring overtake and caught the Frenchman out.

To complicate matters, Quartararo's suit had opened, with the 22-year-old's chest protector also slipping out.

He cut two corners as he battled with Miller for third, and was handed a three second penalty which cost him a third straight podium position at the Catalan Grand Prix.

"What happened I don’t know, I just know that I had the leathers completely open," he explained to reporters.

"I tried to just put it in a normal position again, I couldn't do it. So was difficult to ride, but unfortunately, it happens.

"It happened today, so Alpinestars is looking at how it's possible because at the end of the race it was possible to close it again.

"But it's like this, it was not our day but I can be happy with this fourth position… well, third, but finishing fourth."

Former MotoGP champion Casey Stoner tweeted his thoughts on the incident, insisting Quartararo should have been disqualified from the race.

"Well, I think I already have a penalty that I don't agree [with], demoted three seconds from P3 to P4," Quartararo said when Stoner's comments were put to him.

"I think this penalty is quite enough. It's finished, the race is finished, everything is safe.

"So, I think right now it's not enough to talk anymore because the race is finished. I think there's no point to talk anymore about these possible things."

It was a race which belonged to Oliveira, with the Portuguese rider holding the lead for 23 laps.

"The most difficult thing about the race was the mental ability to stay calm, it was so easy to be aggressive or to just override the tires at the beginning," he said in a news conference.

"I felt like that was the key, stay calm and the race will come to me."

Elsewhere in a frantic race, six-time MotoGP champion Marc Marquez crashed out on Turn 10, which also claimed Valentino Rossi and Aleix Espargaro.

Marquez has now failed to finish the last three races, a career first for the 28-year-old.

Marc Marquez crashed out on the second lap as championship leader Fabio Quartararo claimed a third MotoGP victory of the season at the Italian Grand Prix on Sunday. 

In a race overshadowed by the death of Moto3 rider Jason Dupasquier after a crash in qualifying on Saturday, Quartararo became the first rider to win in Mugello after starting from pole position since 2014. 

Meanwhile, Marquez's hopes of securing a strong result in his fourth race since returning from a broken arm were ended at turn three on the second lap when he made contact with Brad Binder.

Quartararo started from his fourth consecutive pole, but he was usurped by Francesco Bagnaia almost immediately. 

Ducati rider Bagnaia fell from the front on just the second lap, though, handing the advantage back to Quartararo, who fought off the threat of fellow Frenchman Johann Zarco to seal a third win in six races.

This latest victory extended his lead at the head of the standings to 24 points over Zarco, who was leapfrogged by Miguel Oliveria into second with eight laps remaining, with Joan Mir pushing him off the podium soon after. 

Alex Rins pushed Zarco further down the standings, but he was denied a push at a podium place when he crashed on the final corner. 

Oliveira beat Mir to the line for second, although the Portuguese rider was initially demoted to third for exceeding track limits on the final lap. It later transpired Mir had also committed the same offence and they were returned to their original positions. 

TOP 10
1. Fabio Quartararo (Monster Yamaha)
2. Miguel Oliveira (Red Bull KTM) +2.592s
3. Joan Mir (Suzuki Ecstar) +3.000s
4. Johann Zarco (Pramac Ducati) +3.535s
5. Brad Binder (Red Bull KTM) +4.903s
6. Jack Miller (Ducati Team) +6.233s
7. Aleix Espargaro (Aprilia Gresini) +8.030s
8. Maverick Vinales (Monster Yamaha) +17.239s
9. Danilo Petrucci (KTM Tech3) +23.296s
10. Valentino Rossi (Petronas Yamaha) +25.146s

CHAMPIONSHIP STANDINGS

Riders

1. Fabio Quartararo (Monster Energy Yamaha) 105
2. Johann Zarco (Pramac Racing) 81
3. Francesco Bagnaia (Ducati Lenevo) 79
4. Jack Miller (Ducati Lenevo) 74
5. Joan Mir (Suzuki Ecstar) 65

Teams

1. Monster Energy Yamaha 169
2. Ducati 153
3. Pramac Racing 102
4. Suzuki Ecstar 88
5. KTM Factory Racing 64

What's next?

The Barcelona-Catalunya circuit plays host to the next race in the championship next weekend, with Quartararo looking for a repeat performance of his win there last year. 

Jack Miller won the Spanish Grand Prix as the Ducati rider notched his first MotoGP victory since 2016.

The Australian made a superb start to lead and, despite being passed by Fabio Quartararo (Monster Energy Yamaha) in the middle stages, he held his nerve in the second half of the race to return to the front.

Miller finished ahead of Ducati team-mate Francesco Bagnaia with Franco Morbidelli (Petronas Yamaha SRT) in third spot.

Quartararo slipped down to finish 13th as he surrendered his place at the top of the world championship to Bagnaia.

The Frenchman started poorly as he slipped from pole position to fourth as Miller surged ahead, but like the Portuguese Grand Prix last time out he initially recovered.

Quartararo overtook his rivals on the final corner of successive laps to regain the lead before he pulled one-and-a-half seconds clear at the front.

With 11 laps to go, a third consecutive victory seemingly beckoned for Quartararo, but he dropped two seconds on one lap, allowing Miller to seize the advantage.

Miller was able to hold on until the end as he secured his first MotoGP win since the Dutch TT at Assen in June 2016 and his eighth overall.

Quartararo lost further ground as Italian duo Bagnaia with Morbidelli scrapped it out for second, with the former edging it to make it a one-two for Ducati.

Six-time MotoGP champion Marc Marquez (Repsol Honda) returned to the Jerez track where he suffered a broken arm last July –  an injury that kept him out for nine months – and came through unscathed.

Marquez, who had escaped injury in a big fall on Saturday and another accident in warm-up, started the race in 14th spot and eventually ended in ninth in his second race since returning.

Takaaki Nakagami (LCR Honda Idemitsu) claimed fourth place as Joan Mir (Suzuki Ecstar) and Aleix Espargaro (Aprilia) both secured top-six finishes.

TOP 10

1. Jack Miller (Ducati) 41'05.602
2. Francesco Bagnaia (Ducati) +1.912
3. Franco Morbidelli (Petronas Yamaha SRT) +2.516
4. Takaaki Nakagami (LCR Honda Idemitsu) +3.206
5. Joan Mir (Suzuki Ecstar) +4.256
6. Aleix Espargaro (Aprilia) +5.164
7. Maverick Vinales (Monster Energy Yamaha) +5.651
8. Johann Zarco (Pramac Racing) +7.161
9. Marc Marquez (Repsol Honda) +10.494
10. Pol Espargaro (Repsol Honda) +11.776

CHAMPIONSHIP STANDINGS

Riders

1. Francesco Bagnaia (Ducati) 66
2. Fabio Quartararo (Monster Energy Yamaha) 64
3. Maverick Vinales (Monster Energy Yamaha) 50
4. Joan Mir (Suzuki Ecstar) 49
5. Johann Zarco (Pramac Racing) 48

Teams

1. Monster Energy Yamaha 114
2. Ducati 105
3. Suzuki Ecstar 72
4. Pramac Racing 65
5. Repsol Honda 40

What's next?

Quartararo will hope for more luck on home turf at the French Grand Prix at Le Mans on May 16.

Fabio Quartararo overcame a poor start to win a dramatic Portuguese Grand Prix that saw Marc Marquez finish seventh on his long-awaited return.

Marquez said he was ready to "suffer" in his first race since sustaining a season-ending broken arm last July, but the six-time MotoGP champion enjoyed an encouraging comeback after making an early move from sixth to third.

However, it was Quartararo who took the victory, despite dropping down the field from pole position in a pulsating start, after Johann Zarco and Alex Rins crashed out in quick succession at the Algarve International Circuit on Sunday.

Quartararo took over from Zarco as championship leader after sealing back-to-back wins following his triumph in Doha, with Francesco Bagnaia and Joan Mir taking second and third place respectively.

Maverick Vinales could only finish back in 11th place on a great day for Quartararo.

Zarco darted up the inside in a dream start from third on the grid to take the lead from Monster Energy Yamaha rider Quartararo, with Marquez also impressing during the opening laps in Portimao.

Quartararo dropped back to sixth and Marquez caught the back of Mir's Suzuki as he slipped back following a promising beginning to the race.

Rins, who started in second, moved passed Pramac Racing's Zarco in a flash at Turn 13 to hit the front before Jack Miller and Miguel Oliveira - winner on home soil last year - crashed out.

Quartararo had ominously put a disappointing start behind him to apply the pressure, becoming the latest leader of the race with 17 laps to go.

Rins tried his best to cut the gap in second place but spun off 11 laps from the end at Turn 10 after Valentino Rossi had crashed out from 11th place.

Quartararo was in complete control when Rins spun and a second-placed Zarco hit the deck, with Ducati rider Bagnaia holding off Mir for second, having been back in 11th, as the early championship lead changed hands.

Marc Marquez will start from sixth on his MotoGP return, but there was drama and controversy at the front of the grid in Portuguese Grand Prix qualifying on Saturday.

Six-time champion Marquez will race this week for the first time since the 2020 season opener.

The Repsol Honda superstar broke the humerus in his right arm in that event in Jerez and failed in his bid to make a swift comeback, instead watching the remainder of the campaign from the sidelines as Joan Mir claimed his crown.

Marquez has taken precautions at the start of the new MotoGP year, too, missing the first two races, but he is back in action at the Algarve International Circuit.

His previous appearance in Portugal, at Estoril in Moto2, ended in victory in 2012.

Still recovering his fitness, Marquez said: "Tomorrow I'll suffer. But then next week I can recover, then Jerez be a little bit stronger."

A solid Q2 time of one minute and 39.121 seconds was sixth-fastest to ensure a competitive Sunday start, although Marquez would have only made seventh had Francesco Bagnaia's sensational time not been struck off.

Bagnaia, who claimed a first career pole at the season opener, believed he was set to start from the front of the grid again after shattering the track record. The Italian already has three fastest laps over the past two seasons.

But the factory Ducati rider passed through a yellow flag zone following Miguel Oliveira's crash in completing a 1:38.494 lap.

Fabio Quartararo was the beneficiary when that effort was cancelled, promoted to pole as Bagnaia fumed.

"For sure [the flag position is a problem], because you are coming from the downhill and the yellow flag was on the right side," said Bagnaia, whose strong start to the season has included 26 points from two races. He had 47 from 11 in 2020.

"I was already leaning for the corner and preparing for the corner, so it was impossible to see my side.

"[Luca] Marini, who was behind me, said to me the same. He also didn't see the yellow flags, so it was impossible."

Quartararo will be looking to protect his new position, having only finished on the podium in four of his past 16 races but won on all four occasions.

Provisional classification

1. Fabio Quartararo (Monster Yamaha) 1:38.862
2. Alex Rins (Team Suzuki Ecstar) +0.089s
3. Johann Zarco (Pramac Racing) +0.129s
4. Jack Miller (Ducati) +0.199s
5. Franco Morbidelli (Petronas Yamaha) +0.241s
6. Marc Marquez (Repsol Honda) +0.259s
7. Aleix Espargaro (Aprilia) +0.307s
8. Luca Marini (Esponsorama) +0.524s
9. Joan Mir (Team Suzuki Ecstar) +0.536s
10. Miguel Oliveira (Red Bull KTM) +0.583s
11. Francesco Bagnaia (Ducati) +0.620s
12. Maverick Viñales (Monster Yamaha) +0.945s