Toto Wolff says he was "impressed" with Pascal Wehrlein for his "courage and selflessness" in informing Sauber that he could not race in Australia.
Wehrlein came in for some stick when he withdrew from the season-opening Australian Grand Prix.
The Mercedes protégé cited a lack of fitness in the wake of the back injury that he suffered at the Race of Champions, and which kept him out of the Sauber at the first pre-season test.
"I feel for Pascal, because he has had all the bad luck," Wolff said.
"I’m impressed with the maturity he has shown to inform Sauber that he wouldn’t be able to perform at the level required in Melbourne.
"That took courage and selflessness, which I know earned him a lot of credit within the team.
"Now, he needs to build up his fitness and come back strong. I have no doubt that when he’s back in the car, he’ll prove he’s still the same Pascal."
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