Germany's [Images] Nick Heidfeld [Images] has been handed the biggest break of his Formula One career by being announced as a Williams driver after weeks of uncertainty.

"Driving for the BMW [Images] Williams F1 team is the greatest opportunity of my career," said the 27-year-old, thrown a lifeline by struggling Jordan last year after being dropped by Sauber at the end of 2003.

Heidfeld was told by team boss Frank Williams that he had got the nod only moments before the launch of the BMW-powered team's FW27 car in a hangar at Valencia airport.

"Actually, when Frank told me I didn't realise immediately," he said on Monday. "I think still now it needs to sink in. It's been a tough few weeks...I think it is difficult for me at the moment to explain how happy I am."

Heidfeld and Brazilian test driver Antonio Pizzonia had been rivals for the drive and Williams said it had been a close decision, closer than the one he had to make in 2000 between Briton Jenson Button [Images] and Brazilian Bruno Junqueira.

Pizzonia, who had a troubled 11 races for Jaguar in 2003, had been the team's leading candidate until BMW suggested Heidfeld test for them. The German made the most of his chance.

"Until yesterday afternoon I wasn't really nervous, but then the closer it came to the decision the more nervous I got," said Heidfeld.

"Frank was just waiting around the corner here in this hangar and he told me about half an hour before we had to go on stage."

WEBBER HAPPY

Heidfeld's new team mate Australian Mark Webber [Images] was clearly happy with the announcement, which avoided a re-run of his unhappy 2003 pairing with Pizzonia at Jaguar.

"I haven't raced Nick that often, I think we've been in different situations," he said.

"But he's very fair, very professional, races well, races hard, very consistent, knows how to bring the car home and is just absolutely what the doctor ordered for us."

Heidfeld now finds himself for the first time at former champions with a potentially winning car but the irony is that it will be powered by BMW rather than rivals Mercedes.

Known as 'Quick Nick' from early on in his career, the unassuming German was heavily backed by Mercedes on his way to the Formula 3000 junior title in 1999 while also serving as McLaren test driver.

But Heidfeld's hopes of landing a top Formula One drive with McLaren were shattered in 2001 when the Mercedes-powered team overlooked him in favour of his then Sauber team mate Kimi Raikkonen [Images].

While Raikkonen challenged for the title in 2003, finishing as runner-up to Ferrari's [Images] Michael Schumacher [Images], Heidfeld had to fight for his future.

"It's definitely the big step for me," said Heidfeld. "It was great at the end of last year to get called and have the chance to test with the team.

"I knew I had to give it the best shot and I'm really happy that it worked out," he added. "My goal is to win the world championship in the future...but at the moment all I can say is that I will do my best."

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