Hamilton handed five-place grid penalty

Lewis Hamilton will have to do what no Formula One driver has ever done to win Sunday's Bahrain Grand Prix after an unscheduled gearbox change left the Mercedes driver facing a five-place grid penalty.

While the four-times world champion cannot now start on the front two rows, the floodlit race at Sakhir has never been won by anyone starting lower than fourth since it was first held in 2004.

A Mercedes spokesman confirmed Hamilton would have a new gearbox for final practice and qualifying, incurring an automatic five-place penalty.

Gearboxes must last for six successive races according to the rules.

The Briton had been off the pace in the day's two free practice sessions, ending up the fourth fastest in the evening.

"(Hamilton) will take a five place penalty. We had an hydraulic leak in (the last) Melbourne race and were fortunate to finish the race," a Mercedes spokesman said.

"Unfortunately we couldn't repair the box within the six race cycle so need to take a fresh one, incurring the grid penalty."

Hamilton finished second in the Australian season-opener two weeks ago, after storming to pole position.

The race was won by Ferrari's Sebastian Vettel, thanks to a stroke of luck provided by the deployment of the virtual safety car at just the right time for the German, also a four-times champion.

Ferrari were one-two at the top of the end of day practice time sheets in Bahrain on Friday, with 2007 champion Kimi Raikkonen ahead of Vettel.

Hamilton is still on course to rack up his 27th successive points finish, a result that would equal Raikkonen's all-time record.

The Briton's team mate Valtteri Bottas took pole in Bahrain last year, the fifth year in a row that a Mercedes driver had done that, but Vettel won the race.