Russell replaces Hamilton at Mercedes after the 2020 champion tested positive for COVID-19 and will sit out the event.
Aitken, meanwhile, makes his F1 debut; he’s been Williams’ reserve driver in 2020 and generally competes in Formula 2.
“Firstly, I want to say a huge thank you to everybody at Williams for giving me this opportunity,” Russell said in a team release. “I might be wearing a different race suit this weekend, but I’m a Williams driver and I’ll be cheering my team on every step of the way. I see this as a great chance to learn from the best outfit on the grid right now and to come back as an improved driver, with even more energy and experience to help push Williams further up the grid.
“A big thank you also to Mercedes for putting their faith in me. Obviously, nobody can replace Lewis, but I’ll give my all for the team in his absence from the moment I step in the car. Most importantly, I wish him a speedy recovery. I’m really looking forward to the opportunity and can’t wait to get out on track this week.”
“I’m absolutely over the moon to have the opportunity to make my debut with Williams this coming weekend and I am extremely happy for George to have his chance too,” Aitken said. “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, 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.”