Movistar Yamaha’s Valentino Rossi the state of surface at Austin’s Circuit of the Americas is now in a critical condition as bumps that were meant to be removed by a diamond-grinding process are still in evidence.

The Doctor has likened it to riding motocross and says his fairing even scrapes the tarmac at turn 18 because one bump is so big. This, allied to dust and rocks laying on the track, made for an difficult opening day in Texas.

“The situation of the bumps is critical, it’s a disaster. For me, it’s the worst situation of the whole season. Because you have three or four bumps which are very big, because with our bumps it’s very difficult, because you have a lot of bumps in the straight,” said Rossi, speaking at the track.

“The bike moves very much at more than 300 km/h and it’s a critical situation. Also the grip is not fantastic, but it looks like it improves practice by practice, but I’m more worried about the bumps.

“Last year we asked to do some improvements, they did something, but unfortunately it doesn’t work. So the situation with the bumps is critical.

“Turn two is very bad. turn ten, big bumps. And back straight, when you go up after the dip, you go over the crest in fifth and sixth, the bike moves a lot because there are big bumps, a lot of bumps in the braking also.

“And big, big bumps, maybe the biggest one is turn 18, before the last two lefts, you touch the fairing on the ground, so it’s like motocross. It’s a shame, because personally I like this track very much, it’s very good, but the bumps start to be a problem.”

Pramac Ducati's Jack Miller agreed, saying he was doing jumps down the long back straight: "The traction control and wheelie control just starts having a fit because basically you're jumping the whole way down the back straight.

"The rear tyre and front tyre are coming off the ground all the time, so the bike's like cutting in and out and it's just a pain in the arse.

"And then turn two has just got like a couple of whoops coming into it and the same coming out of turn 18. Big, big rollers. For me the bumps on the exit of 18 have been made a lot bigger than last year."