An extraordinary pit-lane blunder by McLaren cost Lewis Hamilton a second successive victory as Brawn GP's Rubens Barrichello took the chequered flag at today's European Grand Prix in Valencia.

Pole-sitter Hamilton was leading the Brazilian veteran by around four seconds prior to his second stop on lap 37 but his afternoon came unstuck when McLaren's mechanics failed to have a new set of tyres ready.

The incident cost Hamilton around six seconds and allowed the hard-charging Barrichello through for his first victory since the 2004 Chinese Grand Prix.

A great day for Brawn was made better by Jenson Button's damage-limiting drive to seventh, ahead of his nearest rival in the drivers' standings heading into this weekend, Red Bull's Mark Webber, who finished outside the points in ninth.

Webber's team-mate Sebastian Vettel suffered an engine failure for the second day in succession to bring a premature end to his afternoon, and Brawn come away from Spain looking stronger than ever to claim both world titles.

Button's lead in the drivers' championship is now 18 points over Barrichello, while Webber is now 20.5 points back and Vettel 25. Brawn are 27.5 points clear of Red Bull in the constructors' championship.

Ferrari's Kimi Raikkonen produced a solid drive to third place from sixth on the grid while McLaren's Heikki Kovalainen failed to deliver on his front-row start as he came home fourth.

Williams' Nico Rosberg produced a typically consistent drive to fifth ahead of Renault's Fernando Alonso, while BMW Sauber's Robert Kubica took eighth and the final point.

But the day belonged to Barrichello, who celebrated his 10th career win with characteristic emotion on the podium.

"It's been fantastic," said the veteran of 281 grands prix.

"It's been a weekend that I will never forget, especially because after five years, it's tough.

"Although you are pushing, there are some things that go through your mind - you want to do it for yourself, for your family and for your country."

Hamilton, meanwhile, refused to point the finger of blame at his team for the pit-lane error which cost him a shot at victory.

"We win and lose together," he said.

"We had a great team effort to get here, so we cannot at all take second place for grated, or be disappointed that we did not get a win.

"I still believe it was a tremendous effort, and these things happen."

At the start, Hamilton made a clean getaway from pole but further back Button suffered a miserable start.

Starting fifth on the grid, the world championship leader dropped to eighth after struggling through the first couple of corners, while a lunge on Alonso failed to come off further round the lap.

Button's tribulations in the pack prompted Webber to come on the team radio claiming the Briton had cut a chicane, and on lap five Webber swept past him for eighth after Button's team told him to give up the place to avoid a penalty.

Vettel's doomed afternoon suffered its first setback on lap 15 when a problem the Red Bull fuel rig at his first stop meant no fuel went into his car and he had to complete another lap at a slow pace before finally refuelling and emerging down in 15th place.

The German's race lasted just another eight laps, however, his Renault engine letting go once again following its failure in practice yesterday.

After running third early on, Barrichello was on the move on lap 20, the Brazilian stopping four laps later than Kovalainen and getting ahead of the Finn.

And second became first on lap 37 when Hamilton suffered his setback in the pit lane.

All appeared calm when the 24-year-old pulled into his pit box as fuel went in and his used tyres came off, but it quickly became clear there were no fresh tyres to go on and the Briton lost crucial seconds while a set was brought out and the warmers removed.

Barrichello, who had been on the pace all weekend as his Brawn thrived in the sweltering Spanish heat, duly swept through to take a comfortable lead, which he held after his second pit stop and all the way to the flag, his margin of victory over Hamilton just under four seconds.

Elsewhere, It was another bad day for stand-in Ferrari driver Luca Badoer, who suffered a spin and a drive-through penalty for crossing the pit-lane exit line on his way to 17th and last of the finishers on the track.

French debutant Romain Grosjean also suffered a spin in the Renault but was rather more impressive than Badoer on his way to 15th place at the flag.