Rob Smedley, Head of Performance Engineering: It's quite hard to read today because of the nature of this track, and with everybody struggling to get the tyres to work. Either the fronts weren't working, or then suddenly they would work and you get oversteer, which we saw from FP1 to FP2 on those running the medium tyres. Overall it's been a fairly quiet day for us. We completed all of the work we needed to, and I'm reasonably happy with where we are on both low and high fuel. There was quite a lot of graining on the soft and supersoft for everybody, but we seemed pretty good both this morning and this afternoon in having relatively low graining, especially on the front tyres. The focus for tomorrow will be on getting our low fuel set-up right and I'm confident that we have a good direction for that.

Valtteri Bottas: I think it was a good day for us. We definitely still have a lot of work to do with the balance; the track was obviously improving a lot so the feeling of the car gets better and better with every single lap. The long runs seemed to be competitive with the supersoft and the medium, so hopefully we're looking at a good weekend ahead for us. We still need to make sure that we work hard tonight to make the changes we need to get more performance.

Felipe Massa: It was very difficult to understand the tyres today. The track is just very low grip, but it's improving every time we go out. You can go out and have no grip, but then suddenly at the end of the run the grip improves. So, I think understanding the tyres this weekend will be very important for the result at the end of the race. I wasn't happy with the result on the new tyres, but I was happy on the longer runs. We just need to work on understanding everything.

Check out our Friday gallery from Mexico City, here.