Jenson Button: "It was a positive afternoon. I did a good lap on the Option tyre, the car is running well, and our upgrades seem to be working. But there are still some improvements to be made.

"The Option seems to be a bit easier for everyone as it's softer and therefore more receptive to generating temperature. In P2, we also started to find a way to get the Prime to work, but then, later in the session, we couldn't quite get back to that sweet-spot.

"If we can solve these issues with the Prime and get it into its correct working range, I think we can be quite competitive this weekend.

"There are a lot of quick cars out there, but, aerodynamically, I think we've got a strong car. We've just got to make sure that we make sure that the four things touching the road are working properly for us too."

Lewis Hamilton: "The car already feels better than it did at the last race - there's a good series of improvements within the car. My long run this afternoon was very satisfying and there are positives to take from that, but there's still more time in the car, as Jenson showed.

"I struggled a little with set-up today. It's a little bit inconsistent, so it's very difficult to pinpoint exactly what's needed to make it better. But we'll be looking at the data to find out where the most significant issues are, and I'm confident we can make improvements overnight.

"Nevertheless, the upgrades we brought to this race seem to be working well and we've got good pace on the longer runs. The guys back at the factory did a fantastic job. It's been a positive day and we're in the fight."

Martin Whitmarsh, Team Principal: "It's pleasing to hear both drivers express their initial satisfaction with the suite of upgrades we've brought to the circuit this weekend. It's now time for the engineers to sit down and look in detail at the data to determine what's working and in what areas we can make further improvements.

"The Circuit de Catalunya is always a very stern test of machinery, so it's gratifying to see Vodafone McLaren Mercedes assume the top spot on the timesheets at this early stage of the weekend. It was a very strong lap from Jenson.

"Looking deeper at the timesheets, it's clear that, once again, we're set for an extremely finely pitched and closely fought race - it's going to be a fascinating weekend."

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