Danilo Petrucci had some strong words for the condition of the Circuit of the Americas after day one of the Austin MotoGP.

Prior to the event, industrial grinding machines were used to try and reduce the notorious bumps - but Petrucci was one of several riders who said they are worse than ever.

"Here we struggle a lot on the bumps. They say they shave the bumps, but maybe they shave in another circuit because the bumps are much more than last year," he said.

"I think it's not safe to race on a track like this. I mean we are in a world championship and I never found a track like this even in the national championship.

"For sure the world championship is the hardest one of the world - and we have to race in every condition and every track.

"But crashing because of bumps I think is a thing that maybe Hailwood and Agostini had in their careers! And today, a lot of crashes for the bumps."

Perhaps part of the Pramac Ducati rider's disappointment was down to just missing out on a top ten place.

The Italian was ranked 13th and then 11th (+1.290s) in the two dry sessions, which could decide the direct places for Qualifying 2 should the forecast rain arrive in Saturday.

"To stay in the top ten would have been a help for tomorrow because of the weather forecast of some rain," he confirmed.

"Anyway our situation is not good, we are so far on the race distance with the race tyre. Even if we try only the soft one and maybe it lasts for us all the race. So we'll see. For sure it’s the situation like Qatar where the bike is very fast."

Fellow GP18riders Jorge Lorenzo and Andrea Dovizioso, of the official Ducati team, were seventh (+0.888s) and eighth (+1.0488s) on day one.