The pace is rapid: fastest time from Mercedes driver Valtteri Bottas in FP2 was nearly a second quicker than the equivalent time from the same session last year.

Another frontrunner was Haas, which showed potential to be just behind the two top teams in both free practice sessions.

We're seeing some degree of degradation as expected; especially on the soft tyre.

There appears to be a tactical difference already: while the soft tyres were used by everyone, there was a roughly 50-50 split of teams running the medium and the hard in FP2. This might mean that different teams are considering varied strategic approaches, assessing long run performances on the hard and medium as well.

Barcelona is renowned for being a high-energy track, but tyre behaviour and performance remained in line with expectations.

Track temperatures were warm today, peaking at 47 degrees centigrade: around 15 degrees warmer than what was seen in pre-season testing here at the end of February.

So far, the performance gaps between the compounds are around 0.8 seconds between medium and soft, and 1.1 seconds between hard and medium.

Mario Isola: "There was nothing special to report from the first day of free practice in Spain, which is to be expected as this is a very familiar venue for the teams and drivers. The gap between the top two teams is very close, and Haas has also shown pace that gets close to them on occasions. As always in Barcelona, it's about marginal gains - so preparing well for qualifying is particularly important, as this is not a track where it's particularly easy to overtake. We're happy with the tyre performance here so far, with the only unexpected factor being a slightly bigger gap between hard and medium than we anticipated."

Check out our Friday gallery from Barcelona, here.