Updated with quotes from Lin Jarvis and Massimo Meregalli.

Yamaha management took the unprecedented step of publicly apologising to factory riders Valentino Rossi and Maverick Vinales after the team's ongoing acceleration problems resulted in their worst qualifying in years, at Austria's Red Bull Ring on Saturday.

Despite Tech3 Yamaha's Johann Zarco claiming sixth, Vinales was left eleventh on the grid and Rossi down in 14th, having failed to even reach Qualifying 2.

The latest setback comes after Yamaha's MotoGP win drought reached 20-races last time in Brno, Yamaha's longest barren run since 1998.

"We, as Yamaha, owe our riders and also you, the media, an explanation," Marketing & Communications manager William Favaro told the assembled media, who had gathered expecting the usual daily debrief with Rossi and Vinales.

Favaro was flanked by Yamaha Racing Managing Director Lin Jarvis, Team Director Massimo Meregalli and Yamaha MotoGP Group Leader & M1 Project Leader Kouji Tsuya, who then took over the microphone.

"Today was a very difficult day for us. We are struggling," Tsuya said, confirming that acceleration performance, related to adjusting the power delivery more precisely, was behind the team's troubles at a track they knew would be "the most difficult" for their present weaknesses.

"I have to apologise to the riders for less acceleration performance today."

Vinales had also suffered sensor problems on his machine in practice (while Rossi had a sprocket failure) all of which prompted Tsuya to conclude:

"We are struggling and have to say sorry to the riders. Now we are working hard as ever to find the solution. After this race we have a [private] test in Misano, before Silverstone. And also after Silverstone, we have a test at Aragon to find a solution.

"But at the moment we will concentrate for tomorrow to get a better result for our riders."

Favero added: "We hope it's just the very bottom of our crisis and now we are confident that we will be able to get out of this crisis soon."

Rossi has been saying since last August that main rivals Ducati and Honda have found an advantage in acceleration, related to the electronics, but so far no solutions have been delivered to the race team.

Nevertheless, Rossi remains (a distant) second in the world championship to Marc Marquez, with Vinales fourth in the standings.

Click Here to read Rossi's reaction to the Yamaha apology

Although Jarvis did not speak during the 'public apology', he later explained:

"As Valentino just said, our bike, technically, apart from the problem that we have with managing electronics and acceleration in the low grip scenario, the bike is very good. He's very happy with the base of the bike.

"So we're just missing enough to make the difference between finishing fourth or fifth or the win. It's the same for everybody, but that's what we're missing, and that's what we have to work on. Maybe two tenths per lap."

Meregalli then gave more details about the upcoming tests, revealing they are 'in delay' and that some of the proposed parts for next year are not related to the electronics.

In other words, they are probably engine parts that cannot be used this season due to the development freeze.

"It's testing as well as a matter of time, because OK, we had a plan, a schedule, but unfortunately, we are in delay," said the Italian. "We were supposed to be testing something new at the beginning of Misano, but now we postpone it and we are just hoping that we can test this new setting in Aragon.

"But anyway, Misano, we will start testing something for next year, that is not anything related to the electronics, but there are many areas where we have to improve, even if Vale is very happy with how he rides the bike.

"As Tsuya said, the driveability, or the power delivery is very very important. And this is also where we are working for next year."