Button: Too early for title thoughts

Having won three of the first four races, the Brawn driver is 12 points clear of his second-placed team-mate Rubens Barrichello, but wants a much bigger margin than he has at present.

"You've got to be aggressive at this point in the season," he said. "It might all go wrong, but you've got to be aggressive, because if you potter around and pick up the points, you haven't got a chance when it comes to the end of the year.

"You have to be fighting for a win at every race you go to. If I didn't in Bahrain, we probably would've finished second or third."

Button is concerned that at present it would only take one retirement to destroy his championship lead.

"You have one reliability issue and you've lost 10 points, then I've got a two point lead and that's it," he said. "It can turn around so quickly. We've seen it many times, especially between Michael (Schumacher) and Fernando (Alonso) back in 2006 when they both had an engine problem at the end of the year and it just cost them masses.

"It's so important to be reliable, but my point is that you've got to be very aggressive at this point in the year to get as many points as you can. You can't settle for a second or third. We don't have enough of a lead yet."

But he reckons Brawn can afford to be more measured in its development programme, pointing out that the team was introducing a big upgrade at Barcelona this weekend whereas some rivals had brought an array of smaller upgrades at the preceding races as they hurried to close the gap.

"If you look at McLaren race by race, it's been different at every race," he said. "There are new bits added everywhere on the car. So I think that's why they got so close.

"Whereas we'll be adding a bigger chunk of lap time to the car aerodynamically, McLaren probably won't have any upgrades here. That's the difference.

"It's the way that they have to work because they have to catch us up. Everything that they get in the windtunnel they're going to have to be throwing at the car. Same with Ferrari and some of the other top teams that aren't quite as competitive.

"Whereas I think we can be a little bit more controlled. We have the pace at the moment and everything we put on the car has to be a good amount better. It's no use just getting loads of little bits and throwing them together. it's got to be a controlled update."