Brawn: No qualms about '09 cakewalk

Button has been the dominant force this season and he now enjoys a comfortable lead at the top of the points standings over his team-mate Rubens Barrichello.

And with Brawn GP's updates in Spain having helped it keep an edge over the opposition, and more developments planned for the next few events, the team principal says he is not worried about the prospect of the 2009 season turning into a runaway for his team.

"That's not something I can do anything about," said Brawn. "We are fighting tooth and claw for every race to do as good a job as we can.

"It's a team that's really come together. The adversity of the winter seems to have gelled everyone even more and everything is working like clockwork at the moment. But we're being cautious."

Brawn says that work is ongoing in the factory to bring further improvements to the team's BGP001, with the next major upgrade scheduled for the German Grand Prix in July.

But although the Spanish GP package was a definite step forward, he says there is no guarantee that the next push will deliver as good results.

"You never completely know," he said. "We've got a great group of people, they are working hard. They've all got a target for the German Grand Prix and the past history is they make it.

"We've got a few bits and pieces for Monaco and Istanbul, but the major upgrade is for Nurburgring."

Although Ferrari made a step forward in performance in Spain, Brawn thinks that it is Red Bull Racing that is the team's serious threat for world title glory.

"It looks that way doesn't it? It looks like that's the main two teams, the teams that understood the opportunities with the new regulations and they've got a very strong team - Adrian [Newey], a good group of people and drivers and it looks too me at the moment that they are the main challenge to us. Other teams will come and go during the season, but in terms of the championship and long term, Red Bull look very strong."