Under his direction, Mercedes-Benz enjoyed considerable success in all categories, winning multiple races and championships.

He then moved on to the publishing house Motor-Presse-Verlag in Stuttgart, which was part of the Gruner + Jahr group, where he became head of motorsports for Auto, Motor und Sport magazine before becoming its deputy chief editor in 1988.

While busy pursuing a career in journalism, Haug also raced cars, including the 24 Hours Nürburgring where he finished second in 1985.

Haug maintained Mercedes presence in Group C and later in the DTM and International Touring Car Championship.

In 1994 Haug negotiated Mercedes-Benz entry to the CART championship, and the Sauber-Mercedes cars were now officially powered by Mercedes-Benz badged engines, developed by the company's development arrangement with United Kingdom based manufacturer Ilmor.