'Stupid' Rosberg sorry for error

Rosberg apologises to team

Nico Rosberg apologised to his Williams team after his pit-lane error cost the chance of a podium finish in Singapore.

Rosberg was second and in touch with winner Lewis Hamilton's McLaren when he crossed the white line of the pit lane exit, earning a drive-through penalty.

"That was very stupid from me," said the German, who eventually placed 11th.

"Williams gave me a car to fight for the win. I don't think I could've beaten Lewis Hamilton but I was very stupid and it cost us dear."

Rosberg, who is tipped to leave Williams for a seat at Brawn in 2010, also commended his team for their "very impressive" development of their FW31 car ahead of Singapore.

The night race will go down as yet another weekend where Williams have posted exceptional times in practice and qualifying, but failed to convert a fast car and a promising build-up into championship points.

Maybe we try to find a brain for him Nick Heidfeld on Adrian Sutil

The team lie sixth in the constructors' standings with 30.5 points, 16 adrift of Toyota in fifth.

Rosberg, seventh in the drivers' championship having been leapfrogged by Hamilton in Singapore, has earned all of those points.

BMW will be similarly disappointed as their much-developed car scored just one point, Robert Kubica finishing eighth on Sunday.

The team have continued to work on improving their car despite the manufacturer's imminent withdrawal from the sport, but Nick Heidfeld's race chances were dealt a double blow.

First, his team mixed up the ballast in the car, leaving it below the minimum allowed weight limit during qualifying and resulting in Heidfeld having to start the race from the pit lane.

Once into the race, Force India's Adrian Sutil drove straight into Heidfeld's side while recovering from a spin, forcing the pair to retire with 21 laps gone.

Heidfeld annoyed at Sutil's 'stupid move'

"It was extremely stupid of Sutil. He should look where he goes," raged an angry Heidfeld after the race.

Asked what his team would do next, he added: "Maybe we try to find a brain for him."

Sutil, who has been given an official reprimand and fined $20,000 (£12,500) for the incident, apologised to Heidfeld.

"I didn't see him coming as I was on the move already and couldn't react to it," said Sutil. "But I'm sorry for it. It was a race incident."