Heidfeld gets early chance

The German, who raced for Jordan this year, will run for Williams on Wednesday and Thursday this week as he battles to prove that he has the credentials to join Mark Webber at the team next year.

Heidfeld had originally been due to run for Williams next week but, in the wake of Davidson's planned test falling through, the team has managed to re-arrange its testing schedule to slot the German in sooner than expected.

Speaking to German media when his first Williams test was announced, Heidfeld made it clear that he knows the run will be his only opportunity to prove how worthy he is for the job - and he is not going to let the chance slip through his fingers.

"I'm looking forward to my test with Williams at Jerez," he said. "I'll fully concentrate on the job from now on and want to do the best I can during the test. I want to use this chance to prove myself to the team."

Although there appears to be no movement on Davidson's opportunity with the team, with the BAR and Williams argument based over theoretical options on his services for 2006, sources claim that it is not completely impossible for the Briton to still get behind the wheel of a Williams later this year.

Autosport.com understands that BAR has lodged a fresh offer with Williams for the terms it will accept to allow Davidson to test, and sources have insisted that BAR believes the terms to be acceptable. The source said: "We feel it is a lenient offer."

Such a matter is not likely to resolved in the short term, however, forcing Davidson to sit on the sidelines. BAR is unwilling to let him test development parts for its 2005 car when there remains the possibility of him racing for Williams next year and taking any knowledge that he has with him.

Williams kicked off this week's test at Jerez by itself on Tuesday, with Mark Webber outpacing Antonio Pizzonia with a best lap of one minute 19.036s.