Lewis Hamilton has stood out among Formula 1 multiple world champions thanks to his "utterly unblemished" sportsmanship record, says Mercedes technical director James Allison.
Hamilton has won five of his six F1 world championships with Mercedes against fierce competition including former team-mate Nico Rosberg and four-time world champion Sebastian Vettel.
Hamilton has rarely been accused of dangerous driving or acting in an unsporting fashion on-track, always engaging in hard but fair racing.
Before joining Mercedes in 2017, Allison previously worked with world champions in Michael Schumacher, Fernando Alonso, Kimi Raikkonen and Vettel during stints at Benetton, Renault, Lotus and Ferrari.
But the Mercedes technical chief says Hamilton's integrity made him stand out among the drivers he had worked with through his F1 career.
"I've been lucky to work with people who have had the highest integrity. I do think that is a characteristic that marks out Lewis," Allison said in a video on Mercedes' YouTube channel.
"I think he's one of the oldest drivers on the grid now, still drives like one of the youngest, but he in a career of multiple championships and countless wins, you'll struggle to find a moment on the track where you see Lewis do something ugly.
"You'll see him do many, many breathtaking things, you'll see him do brave things.
"But you won't see just crude, dodgem car, bumper car stuff, or any sort of artifice to the way he drives.
"I hope he manages to keep this going for the remainder of his driving career, because it's an utterly unblemished record.
"I think amongst multiple world champions, it is also unprecedented to have all that success without anything that has even a hint of a shadow of poor sportsmanship hanging over it.
"I think it's impressive."
Hamilton, 35, may be nearing the final stages of his F1 career, but Allison said there were no signs of the six-time champion losing any of his edge.
"There comes a time where the driver's racecraft is still incredibly strong, but that last little extra special something that still gives them the qualifying genius starts to slip through their fingers," Allison said.
"One of the interesting things about Lewis is that's still very much with him.
"He is blessed with extraordinary physical talents to go along with his mental dedication that is quite freakish."