Red Bull duo encouraged by start

Vettel was slightly quicker than Webber on both occasions as the team edged out its title rivals on the opening day in Brazil, but the pacesetter said it was too soon to declare Red Bull the favourite for this weekend.

"I think it was pretty good, obviously it is not the most important thing to be on top of the list on Friday, much more important tomorrow and especially on Sunday, so we will see," said Vettel.

"It looks like it was a good start. The car feels alright and I am not 100 per cent happy yet so we can still improve it and then we see.

"Let's see what the others did, I haven't seen the times, especially in the long runs, so especially in the end of the session it is always a bit of a rush to get out again, and do your final run so we need to see, so it is okay."

Webber was also encouraged by his team's early form.

"It was a good Friday actually," he said. "We got through everything we wanted to. The track was in pretty good shape straight away so we could get down to work.

"Conditions were good today, so we made the most of it. We are not too sure what will happen tomorrow weather wise, but a lot of good information to go through tonight and we are pretty quick so it was a good day."

He played down the significance of Vettel having been ahead of him in practice.

"Look, he went a bit later and it's pretty close, and I think it is pretty even at the moment," Webber said.