Toto Wolff, the Williams shareholder who manages Valtteri Bottas and only last July became an executive director, is leaving the Oxfordshire based team.
The mass-circulation German newspaper Bild reports that the 41-year-old Austrian, a former racing driver, is replacing the recently departed Norbert Haug as Mercedes’ motor sport chief.
He has almost certainly been appointed by the marque’s new F1 chairman Niki Lauda, the triple world champion who - like Wolff - is from Vienna, Austria.
As well as owning shares in Williams, Wolff also has a stake in HWA, the German company that runs Mercedes’ DTM programme.
Mercedes would not comment, and neither would Williams.
But Bild claimed the news is likely to be announced officially at the DTM test in Valencia, which starts on Tuesday.
Reports estimate the value of Wolff’s Williams shareholding at up to EUR 40 million.