China Friday quotes: McLaren

"We've been struggling a little bit with the set-up. It doesn't feel like the car's performing in all the areas we expected: we need to see whether the issue with the car's balance is down to the upgrade or just an unsatisfactory set-up.

"It does feel like we've found some further improvements since Malaysia, and we'll spend this evening looking at what elements of the new package we choose to take forward into the rest of the weekend."

Jenson Button - 3rd: "This morning was reasonably good and the car was working well - it's a good car to drive. For the afternoon, we tried a few things and didn't really improve the balance of the car, so we're going to look at why the changes didn't really give us the improvement we expected.

"The car felt reasonably strong on the prime tyre but less so on the option. So it's not been a perfect afternoon but we have a lot of information on the changes we made, so we can hopefully work on improving the set-up tomorrow.

"It's not as hot as it was in Malaysia, so I don't think the tyres will be as much of an issue to look after as they were in Malaysia. If we sort out the balance tomorrow, we'll be closer to Red Bull."

Martin Whitmarsh - Team principal, Vodafone McLaren Mercedes: "It was a productive day - we spent the morning conducting aerodynamic tests and we limited each driver to just one set of prime tyres. That helped us draw some productive conclusions as we evaluate this weekend's suite of upgrades and decide what to progress and what will need more development.

"This afternoon was a bit more frustrating: neither Lewis nor Jenson really found a satisfactory balance. They didn't feel as comfortable as we hoped they would be.

"But we've got some very good information and, as always, I think our engineers will take every opportunity to look over that and turn it into something productive for tomorrow."