Mercedes has poached two important engineers from F1's dominant world championship team Red Bull, according to the German newspaper Bild.
The report said vehicle dynamics chief Mark Ellis, and simulation boss Giles Wood, have both been poached by Mercedes.
"Not a nice Christmas surprise for Sebastian Vettel!" Bild correspondent Nicola Pohl surmised.
She said both engineers are due to start work at Brackley in June next year.
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