Sergey Sirotkin’s backers, SMP Racing, have said that it was their decision to leave Williams due to poor team performance levels.
Having beaten Robert Kubica to the Williams seat this year, the Russian rookie has now lost his seat to make way for the Pole, who was officially unveiled as George Russell’s team-mate for the 2019 season.
But Sirotkin’s financial backers have insisted that they were the ones who decided that they should no longer continue their partnership together with Williams for another year.
“We took the decision not to continue participating in the Formula 1 world championship in the joint project with the Williams Martini Racing team,” said SMP Racing chief Boris Rotenberg in a statement.
“We were unpleasantly surprised by the team’s performance level at the start of the season, and the car’s development rate also turned out to be not high enough.
“We are satisfied with his work and are currently evaluating options for his racing career going forward.”
Absolutely buzzing to be driving alongside Robert in 2019 🙌
— George Russell (@GeorgeRussell63) November 22, 2018
Sirotkin has confirmed via social media that him leaving Williams marks the end of his Formula 1 career for now.
“Unfortunately I will not be competing in Formula 1 next year,” Sirotkin wrote.
“It was a very long and difficult year, and not everything turned out the way I wanted it to.
“But I kept working, put all my effort and my soul into achieving the merited results.
“And, to be honest, I believe that given the circumstances we have done a respectable job.”
Heading into the final race in Abu Dhabi, Sirotkin has scored just one point all season in a very uncompetitive FW41 car.