Button enjoys 'very strange' practice

"It's been a very strange day of testing tonight," said Button after Formula One's first two night practice sessions on Friday.

"You would expect the conditions to be cooler but this has to be one of the hottest Fridays that we've ever had and it's just so humid. The circuit is interesting to drive and it's very bumpy, which adds to the excitement as the bumps bounce the car all over the place," he added.

The Honda driver finished a promising eighth quickest, and he claimed he could have gone faster if not for understeer with his new tyres.

"We spent both sessions trying to improve the ride quality and balance of the car by testing many different things and the outcome was largely positive.

"We didn't get the best out of the car on my final run with the new tyres, due to too much understeer, but it was still nice to end up eighth quickest. All in all, a good start to the weekend and I'm sure there is still a lot more to come".

Teammate Rubens Barrichello did not have such a positive day after admitting there were too many bumps on the track.

The Brazilian, who spun into the wall in the opening session, finished down in 18th place.

"We worked really hard today but unfortunately our practice was compromised as the car was bouncing and touching the ground so much," he said. "I was a passenger for the second session really as we could not resolve the problem, despite trying many different solutions.

"The layout of the circuit is quite good but it is very bumpy which has been the cause of the problems with our car. The lighting is quite bright although there seems to be a dark spot at Turn 5. Visibility is not a problem although it may be more tricky if it rains."