Troubled start for BMW drivers

The German squad failed to match the kind of pace they showed at the Australian Grand Prix, with Kubica finishing down in seventh position while Heidfeld wound up 10th.

"We have had many problems today," said Kubica, who retired with a gearbox problem from the Australian race. "Some we were able to fix in second free practice, but there is still some more work to do to fix the rest."

Heidfeld echoed Kubica's comments, the German admitting he was still not happy with his car's handling.

"I am not happy with my car yet," Heidfeld said. "Especially at the beginning of the session the balance was not good at all, and the car was difficult to drive.

"Although later we made a step in the right direction, there is still a lot of work to do."

Heidfeld only ran in the afternoon session after third driver Sebastian Vettel carried out testing duties in the morning.