Pascal Wehrlein is not ruling out a potential return to Formula 1 for 2019.
The German was ousted when Sauber signed F2 champion Charles Leclerc to partner his former teammate Marcus Ericsson for this year.
Wehrlein, 23, is therefore returning to DTM, where he won the title in 2015 before moving into F1.
"Unfortunately I didn't get a seat in Formula 1 but DTM has always been an option," he told Auto Bild. "That's why the move is relatively easy for me."
Wehrlein said that losing out at Sauber to the Ferrari-backed Leclerc is not something he regrets because the decision was "not in my power".
"We could not raise €15m (£13.2m) for the year. It's disappointing that it didn't work out but that's the business," he added.
Wehrlein will, however, be Mercedes's F1 reserve driver this year, and he might also combine his DTM racing programme with Super Formula in Japan.
"It may well be that there will be an additional programme as well as the reserve role in Formula 1," Wehrlein admitted.
As for potentially returning to F1 in 2019, Wehrlein is unsure, even though he is not giving up on the series "at least this year".
"It's difficult to plan for 2019 so it's too early to say in which direction it will go," he added.
However, Wehrlein admitted that winning the DTM title again would help his chances of an F1 comeback.
"If I'm right up there again, I think so," he said. "It could put me in a better situation.
"After all, if you drive at the back for two years, Formula 1 forgets you a bit. Hopefully next year I'll be in a good position to find the cockpit that I want."
The 2018 F1 season begins without Wehrlein in March.
