JENSON Button has virtually written off his hopes of British Grand Prix victory in the wake of his worst qualifying run of the year.

In front of a sell-out 100,000-plus crowd at Silverstone today, the championship leader will start from sixth on the grid in his Brawn GP.

After four poles this year, helping him to claim six wins from the opening seven races and a 26-point lead over his rivals, sixth is not what Button was expecting coming into the weekend.

It now leaves him with an uphill task of joining the list of great British winners at the Northamptonshire track, and in what could be the final race at the venue for some considerable time.

"I think it is almost impossible to win. I just havent had the pace all weekend," said a disappointed Button.

"I was hoping for something a bit better. Being sixth is a lot worse than what I thought it would be, so its going to be a difficult race tomorrow.

"The problem is we've struggled with tyre temperatures because it is so cold. We have to hope tomorrow we can get the tyres to work.

"In qualifying I struggled massively with grip - we struggled as a team to do that.

"It is good we are on the front row as a team, but disappointing for me back in sixth.

"In fact, I would be massively disappointed in qualifying sixth if it was anywhere around the world at the moment, not just here."

His closest championship rivals in Red Bull's Sebastian Vettel and Mark Webber, and team-mate Rubens Barrichello, start first, third and second respectively.

It is the first major setback of Button's storming season, and the pressure is seemingly on to produce a result.

Dismissing such suggestions, and knowing he has the support of the fans, Button added: "When I get in the car I don't feel it.

"And it is great having the crowd here. They support you whatever happens.

"I am sure they would love me to win tomorrow, but that's going to be pretty difficult. I think a podium is also difficult.

"I would prefer if it rained. For the crowd it wouldn't be so much fun, but for me it would."