Button: Brawn stronger than in China

The 29-year-old is cautiously optimistic that he will be able to fight for victory in Sunday's race despite the team not having updated the car since the start of the season.

"It was good," said Button of the team's progress. "The first session was not the best and we struggled a bit for balance with the heat. But the afternoon was much better.

"We got a much better balance for the car over the longer runs. Over a single lap we've still got a bit of work. I'm much happier with the balance here than I was in China on Friday.

Button added that he was unsure of where he stood compared to his main rivals, and expects Williams, Toyota and Red Bull to all be strong contenders.

"Williams normally run with less fuel than us on Friday. Red Bull, I'm not so sure. I think they are competitive, but who knows where they stand. Same with Toyota.

"The McLaren looks quicker. I think they were on more fuel than probably the Williams and they're going to be quite competitive also."

Button also underlined the need for the team to take another strong points haul from this weekend, as for the next race in Spain in two weeks the competitive order could be shaken up by most teams bringing in major car updates.

"Hopefully we can have another good weekend here and go back to Europe with some good points," said Button. "Then it all starts getting very serious because a lot of people are going to improving there cars when we get to Barcelona and Monaco. So we've got to get the points on the board now.

"We'll have an update in Barcelona. We've just got to hope it's enough because a lot of teams are going to be updating their cars when they get back to Europe."