BMW Sauber need to improve

BMW Sauber driver Robert Kubica has admitted that the team is slipping behind Ferrari and McLaren Mercedes and has urged the team to improve.

Since the victory at the Grand Prix in Montreal, which clinched the top spot in the drivers' championship temporarily for the Pole, the team's performances have been disappointing.

Kubica said: "I think we have improved less since Australia than everybody else, so that's the reason.

"Also, Renault and Red Bull are closer to us than at the beginning of the season, so we have to find some parts which will give us better handling, better top speed and better pace. If we lose again in the next couple of races, the gap to Ferrari and McLaren... we will never catch them."

He added that while at times during this campaign the car was faster than Ferrari and McLaren Mercedes, at Magny-Course BMW Sauber fell behind by nearly a second.