Mercedes F1 Motorsports Strategy Director James Vowles has praised the 'meticulous' approach taken by Valentino Rossi during his recent debut in the team's title-winning 2017 car.

Vowles revealed that Rossi was particularly strong in braking and corner entry, while also performing admirably on the exit of slow turns. However, the seven-time MotoGP champion was losing time relative to Hamilton in the faster corners.

Rossi was taking part in his first F1 test since 2010 during a unique ride-swap event with reigning Mercedes F1 champion Lewis Hamilton, at Valencia.

“Valentino's approach was very meticulous," Vowles said. "He got the fundamentals right first in terms of getting the car to where he wanted it to be on track and controlling it, and then just intuitively braking later and carrying more speed into the corner, almost like I imagine he does with a MotoGP bike, and it's very impressive to watch.

"It is really the sign of a true master that he's not out of control and progressively finding performance. Throughout the day, he had areas of strengths. One of them was braking late and carrying speed into the corner, he's really good at that.

"Give him another day or two in the car, and he will then be on top of the fundamentals plus the tuning of all of that. There is a lot of performance to come. In slow-speed corners, as in the exits onto the start-finish straight, there he was very good. Where he was a little bit behind Lewis - and it doesn't surprise me too much - is high speed [corners].”

While the F1 testing rules dictated that Rossi drove a two-year old car, Hamilton got to sample one of the Italian's 2019 Yamahas, albeit thought to be have been fitted with softer, commercial spec Michelin superbike tyres.

No official lap times were released, but Sky Sports F1 states that Rossi spun three times on the way to setting a best time 1.5s off Hamilton in the same Mercedes car.

Meanwhile, Hamilton is said to have had one 'little spin' on his way to a best time 4s slower than Rossi had been on the M1, around what is a 'longer' lap compared to the quicker F1 car. For comparison, Michael Schumacher lapped within five seconds of the then Valencia MotoGP record on an 800cc Ducati in November 2007.

“I was very impressed by Lewis’ performance because how many champions of cars could come here and get on an M1, go out there and do themselves proud?" said Yamaha Racing managing director Lin Jarvis.

"The techniques of driving the car and riding the bike are so different but obviously the human skillset of being able to deal with racing and speed, lines and reactions and so forth is common so it’s fantastic to watch.”