The stop-start nature of today's practice sessions, which were affected by a number of red- and yellow-flag interruptions, meant it was difficult to fully assess the host of chassis and power unit changes introduced for this race. We will refine the package ahead of tomorrow's qualifying session.

Fernando Alonso: "It's hard to make direct comparisons between the two engine specs – you'd need to compare both engines on the same day, and that's impossible. Furthermore, the characteristics of the circuit – both here and Monza – are the opposite of what our car likes, which makes comparisons harder. But the dyno and the data tell us there's more power, so we'll keep going and improve the car as much as we can.

"We knew ahead of the weekend that we'd be starting from the last row, so it'll be interesting if the weather changes and we have a crazy race on Sunday. Whatever happens, I will try to learn as much as possible."

Jenson Button: "We're running a new engine this weekend, and it's definitely an improvement – but you never really know how much until you go through all the data, which is a lengthy task.

"Additionally, it's always tricky here in terms of knowing what downforce level to run. I think we're running too much downforce, and we'll need to look at that and put it right for tomorrow.

"Nonetheless, the car got a lot better through the day. This afternoon was much better – the balance is still a little difficult when we're on high fuel, but, on low fuel, the car feels reasonably good. Obviously, we're not fully competitive around here, but the feeling with the car isn't too bad."

Eric Boullier, Racing director: "It's been a tricky day for the whole team. We had a lot of validation and data logging to run through, and the red flags meant that was harder to accomplish.

"Clearly, there's more to come, and you can be well sure our engineers will be trawling through the data this evening to ensure that we optimise both chassis balance and power unit settings for practice and qualifying tomorrow."

Yasuhisa Arai, Honda R&D senior managing officer - chief officer of motorsport: "Today was slightly disappointing. We brought our planned power unit updates, but the two sessions were very busy with red-flag interruptions on the track, as well as testing of the chassis and new aero parts. This meant we were not able to confirm the performance of the car as a whole.

"Hopefully, tomorrow we can run a more efficient practice session, by setting up the car using the data gained today, and preparing ourselves for qualifying."

Check out our Friday gallery, here.