In December 2005 it was announced that he would not be returning to the DTM series to defend his title but instead would test full-time for McLaren-Mercedes during the 2006 season alongside Pedro de la Rosa.
2005 decemberében bejelentette, hogy nem tér vissza a DTM sorozathoz, helyette a McLaren-Mercedest teljes munkaidőben tesztelhette 2006-ban Pedro de la Rosával.