Adrian Sutil: We had a disappointing day. I went out on the first lap of the morning session and straight away we had some KERS issues, which affected the car's balance and power for the rest of the running. In the afternoon the guys fixed this problem, but we then had a downshift issue, which we don't seem to know exactly what it is, and the car was difficult to drive. So we need to understand this problem as it upsets the car, and with reliability and pace not there at the moment, I am a little concerned. But we shall discuss these tonight and work on them for tomorrow.

Paul Di Resta: We got through the programme we wanted. It was quite difficult to find the ultimate set-up, but I think we found relatively where we need to be on old and new tyres, and certainly how to get the wear out of them because they don't seem to be lasting quite as well as in Melbourne. Given that this was my first session here I think that it was productive, so hopefully we can sit down tonight, analyse it and go forward tomorrow.

Nico Hulkenberg: It was a positive Friday session for me. We ran the super hard tyre for first time; it was interesting running and we collected some good data. We successfully carried out some aero work and I got in some good laps, which I was very happy about. Obviously P4 is a good result; it's where we want to be but it's not realistically where we are at the minute. Overall though it was a good session for the team and I am generally happy.

Dominic Harlow, circuit engineering director: We completed our work today despite the high temperatures, particularly in the afternoon, and we are satisfied with cooling levels, which of course tend to be tested here. We have some issues to address with Adrian's car as he had problems on the downshift that affected the stability but will work on those overnight. On the hot track the drivers found quite high tyre degradation and certainly a bit of oversteer as the rear tyres degraded. It's a different scenario to the weekend in Australia, and we'll be looking through the data to define our best set-up for the race considering both the tyre behaviour and the possible weather conditions.

To check out our Sepang Friday gallery, click here.