Racing Point Formula 1 driver Lance Stroll has not taken part in FP3 for the Eifel Grand Prix on Saturday after feeling unwell.
The team says that it will make a call after the session about whether the Canadian will take part in qualifying at the Nurburgring.
The team's reserve driver Nico Hulkenberg, who is already in Germany, has travelled to the circuit and will be on hand if he is required.
A statement from Racing Point said: "Lance Stroll is not feeling 100% this morning and will therefore not participate in FP3.
"His condition will be assessed after the session to evaluate whether he is fit to drive, at which point the team will confirm plans for quali."
Hulkenberg stood in for Sergio Perez at the British GP and 70th Anniversary race when the Mexican had a positive COVID-19 test.
He failed to start the first race after a last-minute engine problem, and finished seventh on his second outing, having qualified third.
Despite not taking part in any free practice sessions the German will be able to step into the car for qualifying as it counts as a practice session.
A similar situation occurred at the 2017 Hungarian GP, when Paul di Resta was drafted into Williams for qualifying when Felipe Massa was not fit to drive.
Hulkenberg drove at the Nurburgring when it last held an F1 race in 2013, and tested a GT car at the venue a few months ago.
One complication is that he will have to have a negative COVID-19 test before he is allowed to enter the paddock. It's understood that he was due to come to the circuit for TV commitments, in which case he would already have had the necessary test.
Stroll's absence from FP3 will also compromise Perez's weekend. With Friday rained out Saturday's session was crucial for all teams, with the tyre testing workload shared out between both drivers, and work for both qualifying and the race crammed into the single session.