Fernando Alonso: "My second session today was cut short because of a power unit problem, so tomorrow I have still quite a bit of work to do to get ready for quali and the race, including testing the Option tyres.

"The problem with the power unit I had in FP2 today means I'll have to have it replaced, and fit the one I used in Mexico, which obviously has rather a low mileage.

"But I'm not frustrated, actually. In fact in some ways I hope I can get as many problems over and done with here, and again in Abu Dhabi, and then have zero problems next year.

"It's a learning process, and sometimes it's a bit annoying, but, really, it's trial and error, and that's the only way to succeed. We're learning all the time; that's the main thing."

Jenson Button: "On Fridays I don't tend to look at the times so much – it's more about the feel. So, well, there's quite a bit of work for us to do. There was quite a lot of grip out there, but we couldn't make use of it all; and we're struggling a bit with overall balance, too.

"Having said that, I'm sure it's more or less the same for everyone, especially with the high tyre pressures we have to run around here. Doing that makes it difficult to make proper valid comparisons, in fact.

"So things aren't perfect, but, hopefully, helped by some good work in some long meetings tonight, we can find a better balance.

"Going forward, I gather there's a chance that it will rain – and hopefully it will, because rain would give us a better opportunity to do better on Saturday and Sunday."

Eric Boullier, Racing director: "The ICE problem that interrupted Fernando's running in FP2 was a bit frustrating, but I guess these things happen.

"We aren't yet able to pinpoint what the precise issue was, but we're working on it.

"For tomorrow we're fitting a power unit Fernando ran in Mexico, so he'll incur no penalty in respect of today's issue.

"On a more positive note, in FP1 we trialled two front-wing developments, both of which looked promising, and one of which we continued with throughout FP2, and may in fact adopt for the rest of the race weekend.

"Other than that, this evening we'll crunch the data we obtained today, in an effort to optimise tomorrow's FP3 and quali."

Yasuhisa Arai, Honda R&D senior managing officer - chief officer of motorsport: "The start of day one at this historic Interlagos circuit started smoothly.

"In FP1, we had a busy aero testing programme with the front wing as the main focus. Both drivers put in solid laps, and as a result we managed to gather a lot of data. We were also able to set up the power unit deployment and engine mapping for both qualifying and the race.

"We had planned for a longer-run session in FP2, but unfortunately Fernando's mid-session engine issue prevented him from doing any more laps. Jenson, on the other hand, continued to gather useful data for race strategy and tyre wear, so we'll look to share this within the rest of the team.

"We're still investigating Fernando's power unit issue, but, in the meantime, we'll change it ready for tomorrow."