The MotoGP 2020 calendar has undergone another revision prompted by the threat of the coronavirus, with Austin ceding season opener status to Argentina and the finale moving to a week later.

An amended calendar was initially presented to the public on March 5, with Austin's Grand Prix of the Americas becoming the first premier-class race on the schedule after coronavirus-related travel restrictions forced the cancellation of the MotoGP round in Qatar, while the Thailand race was pushed back to October.

Soon after, however, the prospect of kicking off the MotoGP season on April 5 at the Circuit of the Americas likewise became increasingly non-viable, following a declaration of a "state of emergency" in Austin and the quarantine lockdown of Italy, where much of the MotoGP paddock is based.

On Wednesday, MotoGP promoter Dorna confirmed the COTA race weekend would be delayed until later in the year "due to the ongoing coronavirus outbreak".

Whereas the Moto2 and Moto3 campaigns have already got underway in Qatar this past weekend, MotoGP is now due to wait until April 19 at Argentina's Termas de Rio Hondo for its first race.

The COTA race is now slated for November 15, the date that previously belonged to the Valencia finale - which has now been pushed back a week to November 22.

The traditional post-race test in Valencia had already been shelved for 2020, but the latest schedule change casts major doubt over the Jerez test as well, it having been scheduled for November 19-20.

MotoGP has announced that the 2020 Japanese Grand Prix at Motegi has been cancelled due to the coronavirus pandemic, with all overseas races on hold till mid-November.

The COVID-19 pandemic has forced MotoGP to go on hiatus since the beginning of March, when it ran the Moto2 and Moto3 races in Qatar after cancelling the MotoGP event.

Since then, six further races have been cut completely for 2020, with the Japanese GP joining the British, Australian, Dutch, German and Finnish GPs on the list of cancelled races.

MotoGP has put plans in place to begin its delayed season with back-to-back races at Jerez on July 19 and 26 pending Spanish government approval.

With series promoter Dorna Sports keen to run as many races as possible this year, it has decided the season will remain European-based until mid-November, with any flyaway races taking place after that if possible to do so.

Commenting on the loss of the Japanese GP for the first time since 1986, Dorna CEO Carmelo Ezpeleta said: “The MotoGP family is working very hard to be able to restart the racing season and hold as many events as possible, and in the safest way possible.

“For this reason, the FIM and Dorna, in consultation with IRTA (Teams’ association) and MSMA (Manufacturers’ association), have decided that, until mid-November, MotoGP will remain in Europe to do as many European MotoGP events as we are able to.

“Therefore, overseas events, if at all possible, should be scheduled after mid-November – which would be too late in the year for the Motul Grand Prix of Japan to be held.

“For this reason it has been decided, in consultation with [track owner] Mobilityland, that the Motul Grand Prix of Japan cannot be held in 2020. I very much thank Mobilityland for the support given to MotoGP.

“On behalf of Dorna, I would also like to thank all the fans for their understanding and patience as we wait for the situation to improve. We very much look forward to returning to Motegi next year.”

Malaysia, America, Argentina and Thailand are the remaining flyaway events not yet cut from the 2020 schedule that could yet make an appearance towards the end of the year.

However, doubts over the US Formula 1 GP in Texas make a visit to the Circuit of the Americas for MotoGP unlikely this year, which would also throw a standalone trip to Argentina into doubt.

Alberto Puig said the team would prioritize the long-term health of Marquez, an eight-time champion, over the risks of further injury.

“We have a long relation and a long period to be together with Marc, and what we want is the safety of the rider first,” Puig said. “We want him to be strong and fit to secure the next years coming and he can be ready to race at his maximum level.

“Marc will try to come back as soon as possible but from our point of view, from our mentality, we have a lot of respect for this guy, for all of our riders, but in particular, we want that Marc understands his healing is very important for us and for him. And that’s why we’re not going to be counting the days to see when he’s coming back.”

MotoGP championship leader Fabio Quartararo says his struggles in the Austrian Grand Prix were a result of a "dangerous" braking issue he'd never encountered before.

Quartararo started the original race from third on the grid, but dropped to last on lap six when he ran straight on at Turn 4, explaining his front brake "was like a clutch".

He took the restart following the horror shunt between his Petronas Yamaha teammate Franco Morbidelli and Johann Zarco from last, and recovered to eighth having just been pipped by Ducati's Danilo Petrucci on the run to the finish line.

However, he was hindered by the same braking issues at the restart despite his team changing "everything" on the bike, which left Quartararo to rue the loss of "easy points" because of the problem.

"[It was] really difficult because we had a technical problem during the first race and in the second," said Quartararo, whose championship lead has been cut to 11 points by race winner Andrea Dovizioso.

"In the first race we go straight on at corner four. I was there in fifth or sixth position, riding quite easy, but in the lap just before I started to feel the brake [going] soft.

"The lap just after, I braked in the same place as normal during all the weekend and my brake was actually like a clutch.

"I grabbed it by four fingers, trying to stop the bike, it was really dangerous.

"We decided to change everything and it was exactly the same in the second race.

"For 18 laps I was trying to do my best, trying to feel confident because sometimes when I was behind the riders I had no brakes, but when I was alone when I overtook Aleix [Espargaro].

"I had one second to Petrucci, I recovered [the gap] really fast.

"When I was alone it was ok, but still the confidence was not good.

"It's a shame because we can't [afford to] lose easy points like this because of a technical problem."

Quartararo admitted the podium was a stretch on Sunday, but still felt fourth "was our position" had it not been for his brake problems.

"Honestly, I can't say we were ready to fight for the podium because the three riders that finished on the podium were really fast," he added.

"It's never easy, but we had the pace to do the top five. I think fourth position was our position."

Quartararo says the only time he has had a brake issue with the Yamaha was during a daytime session in Qatar last year, and immediately after the Austria race began to look into solutions.

"We need to check, the team is working on it because it's not possible that during all last year and all this year, just in this race I have no brakes for the first time," he said.

"It was better to happen in free practice than in the race of course.

"But the team is looking for a solution - even me, I'm looking for a solution for the braking.

"I understand nothing about mechanical issues but I'm looking to help the team."