Brawn: Button can be a regular winner

Button has won three of the four races in 2009 after two difficult seasons with Honda during which he scored only nine points.

Brawn says that although all the elements needed to be a consistent winner existed in Button before, his growing confidence has been crucial in his emerging as a championship contender.

"Jenson is driving so well this year," said Brawn. "He's had the ingredients and the skills that you need and now he is getting the confidence.

"He's realising that winning a race is something that he can do. It's not so easy that you could ever say that winning comes naturally, but he knows he can do it when the environment is right.

"Jenson is exceptional. Even last year with the car we had there were races when I saw flashes of things that were special, but it's about putting it together on a consistent basis.

"All the guys in the team told me he was pretty special, but I wasn't lucky enough to see much of it. Now I am. He's such a smooth driver. You watch him in the car and nothing's happening because everything is under control. He's not exciting in the car because everything is working well."

Brawn added that seven-time world champion Michael Schumacher had always rated Button highly.

"I've spoken to Michael," said Brawn. "He always had lots of respect for Jenson when we were at Ferrari. He has the highest respect for him."

Brawn is cautious about his team's championship chances, despite Button having a 12-point lead over team-mate Rubens Barrichello with Red Bull's Sebastian Vettel a further point adrift.

The team will introduce its first major set of updates at next week's Spanish Grand Prix, which Brawn hopes will ensure it is not overtaken by its rivals.

"We have got a long way to go in the championship - 13 more races," said Brawn. "This is a great start, but all we can do is push very hard for upgrades and improvements.

"You've seen the progress of some of the other teams, so we have to starting hitting our slopes of progress again."