Lewis Hamilton remains worried about the cooling systems aboard his otherwise dominant 2019 Mercedes.
The championship leader's run of dominant form ended temporarily in Austria recently when the car could not cope with the high ambient temperatures.
And it's even hotter so far at Hockenheim, where the mercury heading for 40C on Thursday.
Mercedes said after Austria that it was working on a fix for the cooling situation, and that will debut as part of a bigger car upgrade at Hockenheim.
But Hamilton remains worried.
"If it stays 40 degrees, we have a problem," he said. "If the temperature drops a few degrees, we are still on the limit.
"We have a few little things that should make it better. But our car is so tightly packaged that we can't do very much actually," added Hamilton.
Mercifully for Mercedes, however, the temperatures are forecast to drop for Sunday, and there is even talk of rain.
"On Sunday it should drop to about 27 degrees, so we are not afraid of another Spielberg," boss Toto Wolff told Krone newspaper.