The form of privateer MotoGP rookie Fabio Quartararo has acted as "stimulation" for team-mates Valentino Rossi and Maverick Vinales, believes factory Yamaha team boss Lin Jarvis.
Quartararo, 20, has scored three pole positions and two podium finishes at Barcelona and Assen respectively in his first nine MotoGP races with the Petroinas SRT Yamaha team.
Marc Marquez has now pinpointed Quartararo as his biggest threat for the remainder of the season, along with works Yamaha man Vinales, who won at Assen.
In an exclusive Autosport interview, Yamaha team boss Jarvis said Quartararo, who rides a 2019-spec bike similar to Rossi and Vinales, has given the factory riders a reference to aim for, despite his inexperience.
"He is able to ride the bike without fear, and it looks like without risk because he has only crashed twice in MotoGP, which is truly amazing when you think about it," Jarvis said of Quartararo.
"Marquez is somebody else who shows these characteristics but he has crashed or almost crashed many times.
"It is amazing that Fabio has this speed without making too many mistakes.
"So, I think he has a very good, exciting future - hopefully with Yamaha, and we will do our best to keep him.
"But also for our existing riders it is good to have a benchmark. It is stimulating.
"Normally it is the other way around with rookies but when Valentino and Maverick are having difficulties, we can look at what Fabio is doing - on a bike that is basically the same, or one step lower - and if he can do something then it means we can too."
Jarvis however insisted that Yamaha isn't getting carried away by Quartararo's potential.
He said: "So far, I think he is very exciting, a young rider with high potential that can do great things, but we have to keep our feet on the ground and so does he, because he hasn't won a race so far.
"So, let's keep it in perspective. But I think sometimes an exceptional talent comes along.
"Sometimes there's an exceptional combination of factors where you have the right guy feeling good on the right bike without pressure and it all just works. I see Fabio a little bit like that at the moment."