BERLIN, Germany - Norbert Haug, 60, has admitted he's stepping down as Mercedes' motorsport vice-president due to the team's lack of track success since 2010.However, in an interview with Germany's Bild daily, he denied reports that he was a scapegoat."No, I'm not," said Haug, who served as the German automker's motorsport VP for more than 20 years. "If I had nothing to do with our failures in the last three years then I would have nothing to do with our 2012 victory in China and I wouldn't like that."Then why was Haug axed and not the UK-based team's British principal Ross Brawn? "Because for 22 years I have borne the overall responsibility for motorsport at Mercedes, not Ross Brawn. I am ultimately his superior."Haug accepted responsibility. "The basis of our car was good but the development was poor to very poor."IN GOOD HEALTHHe denied rumours of ill-health: "Thank God, no!" the German insisted. "Three years ago I had thyroid surgery but since then I'm doing very well. I'm totally healthy."He didn't know if his job would now be split into two roles -- German Touring Cars and F1. "I have no information. Maybe there is a very capable professional who can do much more than I can."He laughed as he played down suggestions that ex-drivers such as Michael and Ralf Schumacher or Mika Hakkinen could fill his shoes."Honestly, I don't think they were born to be in the office."