'Schumi's bad form down to poor car'

Schumacher, 43, returned to Formula One in 2010 after a four-year hiatus, but the seven-times world champion has failed to make an impact on the world drivers' championships.

"We have not been able to provide both drivers (Schumacher and teammate Nico Rosberg) in the past three years with a car that was able to win the majority of races," Zetsche, the head of Mercedes-Benz, told yesterday's edition of German daily Bild. "With the engine we were competitive, but not with the car. And it would be completely wrong to reproach either Nico Rosberg or Michael Schumacher."