Williams reserve driver Jack Aitken will make his maiden Formula 1 Grand Prix race start this weekend, replacing the team's regular driver George Russell.
Russell has been recruited by Mercedes to substitute for Lewis Hamilton, after the world champion tested positive for coronavirus on Monday requiring him to self-isolate for the next ten days.
Williams announced on Wednesday morning that it had agreed to release Russell for the weekend.
In a statement, the team said: "Williams Racing can confirm that Jack Aitken will race in this weekend’s Sakhir Grand Prix alongside Nicholas Latifi.
“Our long-term partnership and George’s affiliation with Mercedes is no secret," commented Williams acting team principal Simon Roberts.
"I’m delighted George has this unique opportunity to join Mercedes, the current constructors’ champions.
"We have been working hard to ensure that an agreement could be made with Mercedes to allow him this fantastic opportunity.
"George very much remains a Williams driver and we look forward to him returning to us fresh from this experience and wish him a successful race this weekend.
“We are also thrilled this means we are able to give another British talent in Jack Aitken the opportunity to make his Formula 1 race debut.
"Jack joined Williams [as reserve driver] at the start of this season, and despite COVID-19 restrictions meaning we haven’t been able to interact with him as much as we would like, he has quickly become a much-liked member of the team.
"We look forward to seeing him build on his previous experience driving the car in practice, to see what he can do in a qualifying and race situation.”
25-year-old British driver Aitken himself was thrilled at getting his biggest break yet in motor sport.
“I’m absolutely over the moon to have the opportunity to make my debut with Williams this coming weekend," he said. "And I am extremely happy for George to have his chance too!
"I really mean it when I say I’ve felt very much at home here since I joined Williams earlier this year, so to get my chance to help the team try to achieve that elusive points finish is an extremely satisfying occasion to say the least.
"I’ll be doing all I can to prepare in the coming days," he added. "But truthfully, I feel like I have been ready since Melbourne.
"I also want to wish Lewis well in his recovery, and good luck to George getting the chance to drive the Mercedes this weekend.”
Aitken has already taken part in an FP1 session earlier in the season at the Styrian Grand Prix, as well as competing in FIA Formula 2 with two podiums and eight other points finishes in 2020.
It's not yet known whether Hamilton will be able to get back in the Mercedes in time for the final race of the season at Abu Dhabi the following weekend.