Monster Yamaha's Valentino Rossi has said a 'red alert' on his dash forced him out of the Jerez MotoGP but wouldn't confirm what the problem was.

Rossi, who mirrored team-mate Maverick Vinales with soft Michelins all round, made it to lap 18 of the Spanish race before pulling ouy but was only just inside the top ten.

"The bike had a red alert and stopped. Now they are checking what happened, but we had a technical problem," said The Doctor.

But that was the last of his issues as once again, as the rear tyre difficulty which only affects Rossi reared its ugly head.

"The problem is that for some reason, we are not able to make the tyres work properly. I have a lot of problems," he said.

"Everybody went with the soft rear and if everybody starts with the soft rear, if you start with the medium or the hard, you already have a big disadvantage. Because the other rubber has less grip. So to have a chance, you have to try to work with the soft rear.

For the front, I don't want to say it was a gamble, but we tried the hard and the soft and the difference was very small. So me and Maverick tried to use the soft. Maybe with the hard we could be a bit faster, but it's not a big problem.

"My problem is coming from the rear. The front doesn't make such a difference.

"But for next week, we have to change a lot, we these problems have happened a lot of times during the weekends and during the races. At this moment, we are not able to fix them."