Honda duo still 'understanding' new parts

The Japanese squad are running a new suspension and a new aero package after their introducing at the Jerez test last week.

Button said the car felt more responsive thanks to the new parts, but admitted there is still work to do to extract the best from them.

"Overall we had a good day today which enabled us to further understand the new rear suspension that we will be racing for the first time this weekend," said Button, 16th quickest today.

"We made some positive changes after the morning session to improve the car as I was not happy with the balance when we had very low grip at both ends.

"The changes ensured that the car was a lot more responsive this afternoon and an improvement over how it has felt for much of this season. Our long run pace is looking okay but we have further work to do over one lap as the balance is not quite there yet."

Barrichello finished down in 19th place after struggling with understeer for most of the day.

"It has been a challenging day today, which we expected as we continue the set-up work with our revised rear suspension and new aero parts," he said. "Once the track had improved this morning, we worked on getting the right balance on the car and conditioning the tyres.

"Unfortunately we struggled with understeer and we need to look at the data closely this evening to confirm our direction before qualifying as the lack of overtaking opportunities here makes it important to get a good grid slot."