Jenson Button: "As with any test of an upgrade package, there are positives and negatives to take away from today. There's now a better understanding of the correlation between the track and the wind tunnel. That's positive for the future, but of course we'd always like more. So I think we've moved forwards, but I think the others have too.

"We were limited in terms of the amount of running we could this morning, so there's a lot of data to sift through and plenty of things to change for tomorrow. We need to look at those elements that are potentially working and those that are not helping the overall car balance.

"We need to focus on a couple of areas - but, hopefully, we can improve them a bit by tomorrow."

Sergio Perez: "Today was basically all about the afternoon session, and collecting as much data as we could from some very intense running. It possibly wasn't the day we were hoping to have, but we collected a lot of data for the engineers - that's a positive.

"It was difficult to draw any clear conclusions from today, but the main positive we can take away is that we have a lot of data to feed into our simulation software in order to improve our understanding of the correlation.

"We've made a slight improvement. Once we get a better grip on our understanding of the correlation, I think we'll start making bigger steps. Over the next few races, hopefully we can make more progress."

Martin Whitmarsh, Team Principal: "This morning's showers limited our ability to gather any meaningful data - the track was only really suitable for running on the dry tyre in the last 20 or 30 minutes. As a result, we set ourselves the task of gathering a lot of data during this afternoon's session, which meant there's now a lot of information for our engineers to unravel.

"Considerable credit is due to the men and women back at the MTC who worked so hard to design, manufacture and freight such a large volume of new parts to Barcelona for this weekend - their efforts are often overlooked, but they play a crucial role in our efforts to return to full competitiveness, so hats off to them all.

"For the moment, our focus is on sifting through some very useful data in a bid to move forward if we can in practice and qualifying tomorrow."

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