time world champion Michael Schumacher said he was gunning for an eighth title in his comeback to Formula One racing with Mercedes GP from next season, in an interview published Thursday. “Obviously our only goal can be to fight for the world championship,” Schumacher told the Berlin daily Der Tagesspiegel. “And of course my goal can only be to again stand on the top step.” Schumacher retired in October 2006 and suffered a neck injury in a motorbike accident in February but the German driver, who will be 41 on Jan. 3, said had “no doubt” about his skills behind the wheel. “I never stopped my physical training,” he said. Schumacher signed a three-year deal Wednesday to return to F1 racing with Mercedes GP for a reported seven million euros ($9.9 million) per year. Schumacher's wife voiced support Thursday for the seven-time world champion's Formula One comeback and said the 40-year-old simply needs the challenge. In comments posted on the German driver's Website, his wife Corinna acknowledged that his decision is “turning our family life upside down.” But “Michael simply needs challenges - that's just the way he is,” she added. “I can really understand his decision and, to be honest, I actually think it's great.” Schumacher will be linking up with Mercedes's team principal Ross Brawn, who was the brains behind all of his world titles, and on the grid when the new season starts with the Bahrain Grand Prix on March 14. The German said Mercedes was the natural choice for him. “I think there is no other team for which I would have seriously considered driving,” he said. “It was the combination of Ross Brawn and Mercedes. Mercedes helped me get into Formula One. I am happy that I can give back some of what Mercedes gave me.” Schumacher was 37 when he hung up his racing helmet, having competed in 250 Formula One Grands Prix, 180 of them for Ferrari. He won 91 races, 71 for Ferrari, took 68 pole positions, 58 for Ferrari, and set 75 fastest laps on his way to seven drivers' world titles, including five for the scarlet scuderia. Schumacher retired having just fallen short of Italian Ricardo Patrese's record of lining up in 256 races. He had been due to make a remarkable return last season for Ferrari - for whom he acted as a consultant after retiring - as a replacement for the injured Felipe Massa. But he was unable to race due to persistent neck pain from the February crash. While Schumacher was delighted with his Mercedes link-up, the automaker's works council slammed the pilot's hefty salary as the rest of the company was cutting back and sending jobs abroad. “It is really difficult to explain to people,” Uwe Werner, head of the works council at the parent company Daimler's plant in the northern German city of Bremen, told the Frankfurter Rundschau newspaper. “They are telling us it is an investment in the future. But the staff would have understood it better had Mercedes pulled out of pricey Formula One racing altogether.” Earlier this month, Daimler decided after other cost-cutting measures to move some of its production of C-class cars from Germany to the US city Tuscaloosa. It is unclear whether the move will lead to job cuts here. Meanwhile an automobile industry expert said he doubted the Schumacher deal would pay off for Mercedes. “Mercedes in particular is a company for which sportiness is not a selling point but rather security and quality,” Ferdinand Dudenhoeffer of the University of Duisburg-Essen in western Germany told Bayerischer Rundfunk public radio. “Why should a driver decide to buy a Mercedes because of Formula One?” He said the cost of investing in F1 would have to be passed on to consumers. “Every car will have to be sold for 200 to 300 euros more for Mercedes to finance Formula One.” Mercedes sport chief Norbert Haug dismissed the criticism. “The whole engagement will sell a lot of cars,” he said.