Nico Hulkenberg will race for Racing Point in the 70th Anniversary Grand Prix after Sergio Perez again tested positive for coronavirus.
Perez, 30, missed the British Grand Prix after contracting Covid-19 but the team had hoped he could return.
Racing Point were trying to exploit a technicality in the isolation rules regarding the day of his test.
But the Mexican was positive when tested again at Silverstone on Thursday so is unable to enter the paddock.
The team said Perez was "physically well and recovering" and "would continue to follow the guidance of Public Health England".
Hulkenberg was unable to race last weekend when his car developed a mechanical problem before the start of the grand prix.
Team principal Otmar Szafnauer said: "Nico did a really strong job last weekend after receiving a last-minute call-up to drive for us at Silverstone, and he proved why he was an obvious choice to stand in for Checo.
"It was a big shame he couldn't actually take the start of the race last Sunday, but all that hard work will prove very useful for this weekend. We miss having Checo with us, but we wish him well and look forward to welcoming him back into the team in the near future."
Racing Point have been criticised behind the scenes within F1 for their actions in trying to pursue a return for Perez.
Perez's official positive result for coronavirus was on Thursday, 30 July, when the official guidance stipulated a 10-day isolation period for anyone testing positive for Covid-19.
But Racing Point argued that because his first test - dubbed "inconclusive" by F1 authorities - was the day before, when guidance was for only seven days' isolation, that should apply to Perez.
However, some senior insiders felt that teams should be more aware of the sensitivities around the topic, especially as F1 has had to impose severe protocols on competitors to reassure governments that it was safe to allow the sport to resume.
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