Germany's Nick Heidfeld will race for Williams this season alongside Australian Mark Webber.
Scattered showers marred Nick Heidfeld's test drive for Williams in southern Spain.
Lead mechanic Matt Deane and re-fueler Mick Gomme survived the incident with nothing more than bruising.
The two drivers are vying for a place alongside Australian Mark Webber at BMW-Williams for next season.
Nick Heidfeld joined the Mercedes Formula One team as test and reserve driver on Thursday, completing a trio of Germans in a line-up led by Michael Schumacher and Nico Rosberg.
Nick Heidfeld's test with Williams, due on December 9, has been brought forward to Wednesday.
Heidfeld, 30, and Kubica, 22, have scored 71 points between them this season with BMW now 38 points clear of fourth placed Renault in the constructors' championship.
Nick Heidfeld showed BMW's pace in pre-season testing on Friday with the quickest lap yet of the Bahrain circuit by a 2.4 litre V8 powered Formula One car.
Williams hopeful Nick Heidfeld was fastest at the start of what could be a decisive five-day test programme with the Formula One team in southern Spain on Monday.
Williams' Nick Heidfeld will miss next week's Brazilian Grand Prix after a bicycle accident at the weekend
Germany's Nick Heidfeld was second fastest as he did his best to impress Williams in a wet and windy Formula One test session.
World champion Sebastian Vettel continued his perfect start to the Formula One season by winning the Malaysian Grand Prix from pole position on Sunday.
Heikki Kovalainen and Lewis Hamilton will start the Malaysian GP eighth and ninth after collecting five place penalties.
Brazilian Grand Prix stewards cleared BMW's Sauber's Robert Kubica and Nick Heidfeld and Williams' Nico Rosberg of alleged fuel irregularities.
Sebastian Vettel powered to victory in the Malaysian Grand Prix on Sunday, the German registering his second pole-to-flag win in as many races to open his Formula One title defence.
The record at the Nuerburgring, Germany, venue of Sunday's European Formula One Grand Prix , round five of the 18-race Formula One championship.
McLaren have formally lodged an appeal against the decision not to penalise three drivers in the Brazilian Grand Prix because of fuel irregularities.
Giancarlo Fisichella came close to scoring his first point in a Force India car before settling for a season's best 10th place even though teammate Adrian Sutil had yet another 'Did Not Finish' tag against his name in the incident-strewn Spanish Grand Prix in Barcelona on Sunday.
Ferrari's Felipe Massa needs to repeat last year's dominant victory in Bahrain on Sunday to silence his critics after a poor start to the Formula One season. While McLaren's Lewis Hamilton leads the standings with 14 points, three clear of Ferrari's World champion Kimi Raikkonen and BMW Sauber's Nick Heidfeld, Brazilian Massa is yet to score.
The Canadian driver will lose 10 places on the Australian GP after his team confirmed engine change for Saturday qualifying.
Formula One world champion Lewis Hamilton kept McLaren on top for a third straight practice session at the Hungarian Grand Prix Saturday.
The Formula One team confirmed that the Canadian will line up alongside Nick Heidfeld for the BMW Sauber F1 team in 2006.
McLaren's Lewis Hamilton led the Hungarian Grand Prix from start to finish on Sunday to stretch his championship lead over unhappy team mate Fernando Alonso to seven points.
The decision confirmed Germany's Nick Heidfeld as the eighth placed driver and relegated Ralf Schumacher to 11th at the San Marino Grand Prix.
The Finn pipped the seven times champion by just 0.002 seconds.
McLaren's Lewis Hamilton dominated a wet and chaotic British Grand Prix on Sunday to storm back to the top of the Formula One standings in front of his home fans.
Lewis Hamilton avoided mayhem around him to open the F1 season with a pole-to-flag victory in a crash-strewn Australian Grand Prix.
Germany's Nick Heidfeld was second for Williams with Australian team mate Mark Webber third for his first podium finish.
McLaren's Lewis Hamilton took his first Formula One victory on Sunday, keeping his cool in a chaotic Canadian Grand Prix to take the outright lead in the championship.
BMW's Nick Heidfeld believes F1's return to Europe could force re-writing of the early-season form book
Swedish driver Felix Rosenqvist won the first of two Berlin ePrix races on Saturday to hand India's Mahindra team a maiden victory in the Formula E electric series.
Four years after entering Formula E racing, Mahindra comes out with a racing car designed for the e-racing circuit. Rajesh Karkera/Rediff.com reports.
The 31-year-old German fell 30 points behind race-winner Hamilton after a collision with the Briton left him struggling to finish fourth in Monza last time out, one of several races where Vettel has frittered away a position of authority.