Renault Sport F1 boss Cyril Abiteboul has backed the team's test and reserve driver Sergey Sirotkin to take the vacant seat at Williams in 2018.
The young Russian is believed to be in pole position to take the spot. He was reportedly faster than Robert Kubica in a recent test with the team, and brings with him valuable sponsorship money.
Abiteboul says the 22-year-old would be a good team mate for Lance Stroll, having been impressed with the work he's done for Renault.
"We have always been very impressed by Sergey,” Abiteboul told Motorsport.com. "In terms of pace, in terms of loyalty, in terms of focus, in terms of work, I think he deserves to be given a chance in Formula 1.
"It’s difficult for me to say how strong he would be in a Formula 1 car against any teammate," Abiteboul admitted. "But certainly he needs to be given a chance, absolutely.”
Sirotkin took part in six free practice sessions during his two years with Renault, as well as two test days He also
Abiteboul said a significant proportion of the team's positive development in 2017 had been based on Sirotkin's feedback, from the simulator at Enstone as well as on the track.
"The accuracy of his technical feedback was always extremely helpful," he said. “I think it’s quite amazing, given his moderate experience of Formula 1 cars.
"He was really capable of showing that he had some pace, and also a very strong understanding of the car."
Unfortunately Sirotkin's time in the car during several of those Friday practice sessions was limited more than once by technical problems.
“We have not always been impressed by the luck he has!" Abiteboul said. "I think on two or three of his FP1s he performed for the team, we had some mechanical issues with the car completely unrelated to him."
Hopes that a seat would open up at Renault in 2018 were thwarted when the team opted to sign Carlos Sainz on a one-year loan from Toro Rosso. Now the only seat still up for grabs next season is at Williams.
An expected announcement about the line-up has been postponed until January. However, Sirotkin is still believed to be favoured ahead of Kubica, Daniil Kvyat, Paul di Resta and Pascal Wehrlein.
"If he’s considered by Williams, it’s also thanks to the work we’ve done together," suggested Abiteboul.
“He has some natural skills and natural pace, but in modern Formula 1 those things do not come for free," he continued. "They come also from the effort put in by the team into the driver
"I think we put a lot in terms of mileage in a current car and previous cars, and I think he is a different driver now to what he was 12 months ago."