Rosberg baffled by Williams form

The British team have failed to score any points in the last five races, a streak not seen since the 1984 season, when they failed to score in the last seven races of the season.

Williams have scored just 10 points this year, and lie in eighth place in the standings.

Rosberg's team endured another disappointing race at Indianapolis last Sunday, with teammate Mark Webber retiring after the first corner accident. Rosberg went on to finish the race, but he struggled with the handling of his car and finished ninth and last.

The German admits the team are unsure about the cause of their problems, but he is hoping a return to Europe will help them fight back.

"Everyone is working so hard at the moment that it's quite difficult to understand why we are off the pace," Rosberg wrote in his column for the Castrol website.

"There is no single area which I can pinpoint and say we need to improve that, but we've got a new aero package for the high downforce French Grand Prix and I'm hoping that will make a positive difference.

"There are other reasons to be optimistic as the F1 circus returns to Europe: Magny-Cours is a circuit I'm really familiar with, while Mark and I are working really well as a team so hopefully these positives will combine in France and we'll be back at the sharp end."