Four-time world champion Sebastian Vettel has been ruled out of Sunday’s season-opening Bahrain Grand Prix after testing positive for Covid-19.
The Aston Martin driver will be replaced by Nico Hulkenberg.
McLaren’s Daniel Ricciardo missed the final test in Bahrain last week after contracting coronavirus.
But the Australian is fit for race weekend, which begins with practice on Friday, after returning a negative test.
Aston Martin reserve driver Hulkenberg, 34, has not been a permanent F1 driver since 2019 but has filled in for others.
The German made three appearances in 2020 when he replaced Sergio Perez and Lance Stroll, both of whom missed races because of coronavirus.
The second race of the season is in Saudi Arabia on 27 March. If German Vettel tests negative before then he should be able to compete.