Saturday 6 September at 16:37 : Nick Heidfeld admits he is fighting for his future with BMW-Sauber in formula one.

The 31-year-old German has been at the wheel of the Swiss based team's BMW guise since its inception, but in 2008 he has struggled to keep pace with his teammate Robert Kubica.

He told Bild newspaper that, with the 2009 grid now beginning to form, his situation is "bad".

"I am fulfilling neither my own expectations or those of the team," Heidfeld said.

He was asked by the German newspaper if he fears for his job.

"Yes, I do," said Heidfeld, comparing his situation to when he lost his seat at the Sauber team at the end of 2003.

"There have been two times when I did not know how it was going to continue for me -- a very difficult time," he explained.

Amid reports of contact with Toro Rosso, Heidfeld admits he is currently "observing the driver market, as I always do".

"But I want to remain with BMW next year and fight for the championship. It would be really annoying if I was not able to do that."