Button mystified by lack of pace

The points leader qualified a disappointing 14th, 10 places behind the European Grand Prix winner after being a shock knock-out in Q2.

"I didn't expect to qualify in 14th position today but we really struggled with grip levels, particularly on the softer tyre," said Button. "The car hasn't felt quite right all weekend and unfortunately I wasn't able to get any more out of it today.

"Rubens and I are usually very closely matched but he was quick on the option and I wasn't, so we need to look into the reasons for that.

"I just couldn't find any grip on the softer rubber so the rear end felt unstable and I had no confidence under braking, particularly in the middle sector. It's strange as our set-ups are different but not by much. It's going to be very tough in the race from here but at least we have more time to choose our strategy.

"We need to get it right and see if we can score some points tomorrow."

Barrichello was delighted by the result which gives him a great opportunity to reduce the 18-point deficit he has to Button at the top of the table.

"I'm extremely happy with our qualifying performance today and the second row of the grid is a great starting position for the race," he said. "I took the best out of my car today, particularly in Q2 which was one of my best laps around Spa, but that was only enough for sixth position in that session.

"We've been quite aggressive on the strategy and the race is wide open tomorrow so I'll push as much as I can and we can get a good result from here."