Felipe Massa: It has been a good day today with all upgrades working and improving performance as we had expected. It's hard to see who we will be fighting with come the race as all the teams have made a step forward. There are still some rear grip issues, it has improved since the start of the season, but we are not there yet. The medium is the best tyre for the weekend as we were struggling for grip on the hard tyre, as is everyone else. It's always good to see upgrades working as they have all done which is once again impressive.

Valtteri Bottas: We have had a positive day as the upgrades we brought here have worked as expected, but it's hard to say where we are in comparison to other teams. We will see tomorrow. The rear of the car was a bit snappy at the end of Turn 3 and this was made worse by the tailwind, the grip was also hard to handle in this corner. I didn't have all the updates as Felipe was testing them for comparison, so I'm feeling positive knowing my car will be faster tomorrow.

Felipe Nasr: In the first session we limited our running as the track started off quite green. We have some new parts in the car and so my focus was to analyse how they performed. The car felt good and we found a lot of positives but there is some work still to do on the rear as Barcelona demands a lot of rear downforce. We made some small changes mid-way through the session which resulted in the car becoming harder to drive, which is interesting for me to know how these changes effect the car. Overall it is a positive day for both myself and the team as we obtained a lot of data from the new upgrades.

Rob Smedley, Head of Performance Engineering: It was a constructive day as we had a lot of work to do in terms of car set-up and tyre management as well as testing all the new pieces. We completed the tests we had planned and as a result all the parts we brought are working as expected or even better, which is key at a track like Barcelona where everyone is trying to find more downforce. We still have a lot of work to do in order to optimise our car set-up and the long run pace, and so that is the focus for this evening.

Check out our Friday gallery, here.