It was a busy day for the whole McLaren-Honda team as we evaluated MP4-30 in a number of different configurations in order accurately to measure and assess a suite of aerodynamic, mechanical and power unit upgrades.

Tricky weather conditions, a slower-than-expected track surface, and some difficulties getting the tyres to work this afternoon compounded the heavy workload, meaning that our engineers go into this evening somewhat scratching their heads about what worked on the car today and what didn't.

Nevertheless, the upgrades are contributing to the upturn in performance, and both Fernando Alonso and Jenson Button are optimistic that the car's issues will be ironed out ahead of qualifying tomorrow.

Jenson Button: "You simply can't compare the car I drove today to the car I last tested here back in February; the difference is night and day. Then, the last corner was easy-flat, whereas now it isn't because of the extra grunt our Honda power unit is pushing out these days.

"We felt reasonably good on the Prime tyre this morning, but really struggled on it in the afternoon, when we were much better on the Option. So there's a lot of work for us to do in every area to optimise what we have, and also to figure out why the car is doing certain things on track.

"All in all, it's been a positive but tough day in terms of putting miles on our components: for example, we tried three different front wings today - so the sessions were mainly about data collecting. There's still plenty of room for improvement, so we need to properly study all the data tonight."

Fernando Alonso: "Today felt more like a test day than the Friday of a grand prix weekend. But it's been positive: we ended the day without any technical problems, and we completed everything on our run programme. I had a little spin at the end of FP1 - I was pushing on one of my in-laps, just having a bit of fun, when the car pirouetted at Turn 12.

"The track was a little bit slower today than it was in winter testing, and we had to adapt the car to today's conditions, but hopefully tomorrow we can be a little bit closer to the cars at the front.

"We've made a number of positive steps today, and the car seemed to behave well, but we have a lot of work to do tonight. We need to pull everything together and then select the best parts for qualifying tomorrow."

Eric Boullier, Racing director: "It's been a busy day: we had an extremely aggressive run programme planned for today - with lots to assess and analyse - and, pleasingly, we got through it all.

"It's hard to definitively measure the extent of lap-time improvement that this weekend's upgrades have provided, but we're seeing useful positives in every area.

"Additionally, both Fernando and Jenson have given us some very detailed feedback, but it's clear that we still have some work to do if we're to get the whole package working to its fullest extent on Saturday and Sunday. The most important thing, however, is that we're moving forwards."

Yasuhisa Arai, Honda R&D senior managing officer - chief officer of motorsport: "Today, FP1 was a bit difficult because we were trying to pull together various updates from both the chassis and power unit side - so the 90 minutes went rather quickly!

"In the end both sessions were very productive for us, though, and we were able to test the power unit driveability software updates that we implemented during the mini-break. Based on the FP1 results, we then tweaked the engine dynamics further for FP2.

"On the operational side, things are working more smoothly than they were on the first four race weekends, and we're satisfied with today's work in the garage. We still need to review our data further for tomorrow's running - qualifying is very important at this track, as it's so difficult to overtake here. But, as always, we'll do our best."

Check out our Friday gallery, here.