Five-time World Rally champion Sebastien Ogier is set to make his DTM debut at the Red Bull Ring in Spielberg, Austria next month.
Mercedes have confirmed that Ogier will race in their AMGC63 DTM car at the penultimate round of the 2018 season on September 21-23.
DTM rules allow each manufacturer to run a seventh car for a guest driver, although Mercedes has required an exception to be approved by governing body DMSB and rivals Audi and BMW as guest entries are not permitted in the final three rounds.
"This is a very exciting experience," said Ogier. "The DTM is something completely new for me, but I'm trying to learn as much as possible with each lap.
"I see it as an opportunity to broaden my racing horizons and gain more experience. Up to now, I haven't driven much on permanent racetracks - only a couple of times in a GT car [in GT Masters in 2014].
"A DTM car is obviously faster. Of course, you can't expect to be competitive as a guest starter right away.
"I'm expecting a difficult first weekend at Spielberg, where my target will be to keep up with the other drivers as much as is possible."
The WRC legend will be the third guest driver in 2018. Audi ran an additional car for the retiring Mattias Ekstrom at the Hockenheim season opener, while BMW will enter a seventh M4 for Alex Zanardi at Misano later this month.