Mercedes will make one final appearance as a DTM manufacturer by fielding four drivers in this week's Jerez rookie test.
The manufacturer won the title with Gary Paffett in its final DTM season this year, but was obliged to run cars in the three-day test on December 10-12 as part of its agreement with series promotor ITR.
It will field Blancpain GT Series regular Jake Dennis, GP3 frontrunner Jake Hughes, Porsche Supercup race winner Thomas Preining and Formula 3 driver Ferdinand Habsburg, who switches from rival marque Audi.
Brands Hatch race winner Dani Juncadella, who has not secured his post-Mercedes DTM future, will also be present as a reference driver for the four newcomers.
Habsburg's place in the six-strong Audi line-up will be taken by Carlin European F3 Championship team-mate Sacha Fenestraz.
Both Fenestraz and Jonathan Aberdein will be testing for Audi customer squad WRT at Jerez.
BMW has already announced its four drivers for the test last week as it evaluates a replacement for Augusto Farfus, and will use the Jerez running to continue development on the Class One-regulated 2019 car.
Bruno Spengler and Marco Wittmann will be at the wheel of the BMW, while fellow DTM regular Philipp Eng will serve as the reference driver for the rookies in the 2018 car.
Audi will also use a 2019 prototype for the Jerez test, but has not named any of its regular drivers to attend.
Its testing at Estoril was conducted by Nico Muller, Rene Rast and Mike Rockenfeller.