It's the latest memorable milestone achieved by the popular Italian, who made history with a Dakar stage win shortly after leaving the premier-class at the end of last season.

Familiar with the Austin circuit from his MotoGP days, Petrucci rode his Warhorse Ducati Panigale to a first MotoAmerica win by 1.7s from Matthew Scholtz with Cameron Peterson in third.

"No, sincerely [I never imagined this]," Petrucci said. "My target was to stand on the podium because these guys and also Jake Gagne are really fast.

"After the Dakar I was really tired and broke my ankle and radius on my collarbone, then I broke my knee ligaments training on my motocross bike! I've almost forgotten how to run and feel like I have the legs of another man! So I'm happy but I'm not physically fit.

"In the first part of the lap I was struggling. So I just tried to manage, also with my rear tyre, which was unstable because we only did a little testing and still need to find a set-up.

"But I'm really happy to be here racing with these guys, the atmosphere is really nice. Coming to MotoAmerica is one of the best choices I've made."

The 31-year thus repeated the feat of fellow MotoGP star Toni Elias, who took victory on his MotoAmerica debut, also at COTA, in 2016. Elias went on to be crowned champion the following year, but could Petrucci claim the title at his first attempt?

Race 2 takes place at COTA tomorrow (Sunday), following the three grand prix races.