Rosberg: Williams must keep improving

Williams has made strong progress with its FW31 this year and the team is hopeful that it could soon secure a top-three finish on pure merit.

Although Rosberg recently echoed such confidence, the German does couch it with the belief that the team will need to keep making improvements to its car.

"Our performance at Silverstone, in fact in Turkey as well, has given me lots of optimism," said Rosberg. "The team are doing a really good job in terms of development and that is showing on the track.

"At Silverstone, we had another fifth place and those points moved us up another position in the constructors'. We need to keep making that kind of progress for the rest of the season now. Hopefully, we'll be on the podium soon."

Team-mate Kazuki Nakajima is equally upbeat that a good result is just around the corner - even though he has expressed some frustration at opportunities that have slipped through his fingers in recent races.

"Silverstone was a good race weekend until the first stint when it was really difficult to make any progress and we missed some opportunities, we cost us a place in the points," said the Japanese. "It's not a case of having to try harder; it's just waiting for it to all come together."