On its first visit to the Circuit of the Americas, the supersoft tyre has gone quickest in free practice, with Mercedes driver Nico Rosberg setting a fastest time of 1m37.358s early in the afternoon session.

Conditions in FP1 were cool and so not very representative. In FP2 track temperatures were considerably higher (peaking at 41 degrees centigrade). This is typical of Austin, where temperature swings at this time of year are commonplace.

The supersoft and soft tyres are separated by one second so far, with the supersoft, as expected, experiencing greater degradation. This means that the first stint for those starting the race on supersoft tyres might be quite short: potentially encouraging some teams to try and start the race on the soft tyre by running it in Q2 tomorrow.

Paul Hembery: "From what we can see so far there is around a one-second performance gap between the supersoft and the soft in these conditions. The medium compound is also about a second slower than the soft, which makes it quite an interesting choice for the race. We saw a high degree of track evolution compared to 2014, with rain dominating the conditions last year. There seem to be a number of strategy options: especially because this is a track that you can overtake on."

Check out our Friday gallery from Austin, here.