Lewis Hamilton has been dealt a huge blow in his bid to win the Bahrain grand prix after being handed a five-place grid penalty. The FIA confirmed on Friday evening that Hamilton's gearbox had been replaced ahead of Saturday's final practice session, breaking the cycle of six consecutive races a gearbox is required to last under the regulations. As a result Hamilton will be issued with a five-place grid penalty on top of his qualifying position.
Mercedes said the problem was caused by a hydraulic leak in the gearbox and that Hamilton was lucky to finish the race in Melbourne.
The gearbox rule is in the regulations as a cost-saving measure and is intended to limit the amount of expensive drivetrain components fitted to a car over the course of a year.
The rule only applies to the Saturday and Sunday of a race weekend, meaning the gearbox fitted to Hamilton's car during Friday practice would not have been the one that failed.
Speaking before the penalty was announced, Hamilton said: "We've got things to improve on. What it's just shown is that it's incredibly close between the three teams, like really close. I think it will be a tough weekend.
"I think we're going to have to look upwards and you'll see that the Ferraris seem to be a little bit quicker on the straights. So you could argue that it's a little bit of power but then a little bit of downforce."
