Jenson Button believes his hopes of winning in front of his home crowd at this weekend's British Grand at Silverstone have been diminished by the pace of the revised Red Bull RB5s in free practice.
Sebastian Vettel and Mark Webber dominated Friday's practice sessions and Button, who has won six of the seven races run this year, says that their speed was not just down to usual vagaries of teams working through different programmes.
"Even if we sort the car out we are not going to be as quick as the Red Bulls, they are just staggeringly quick around here," he told reporters on Friday afternoon. "I don't think we are going to find that pace overnight.
"If it is warmer I think it will help our car because we not getting temperature in the tyres, but hopefully we can race the Red Bulls because that is what we are here to do."
Button revealed that he had struggled to get temperature into his tyres, but added that even if they get the Brawn dialled in, he was not sure that it would enough to close the gap to modified Red Bulls.
"It's nice racing in your home country and in front of your fans," he said. "Hopefully we can have a good weekend, but if we don't we don't. In the big scheme of things winning here would be fantastic from the emotional side.
"We will see what happens, at the moment we are not quick enough compared to the Red Bulls.
"We have just got to hope that we can improve the car and work long hours this evening to improve the car and make it competitive.
"I don't think it is going to get much warmer over this weekend, and the heat would help us because we are not getting any tyre temperature. We know the Red Bulls work very well with a low circuit temperature."