The Formula One season resumed at Spa-Francorchamps in cool conditions: a common feature of the legendary seven-kilometre venue in the foothill of the Ardennes. Track temperatures climbed to just 30 degrees centigrade in the afternoon, with ambient temperatures hovering around 18 degrees centigrade.

Mercedes were first and second in both free practice sessions, with Nico Rosberg fastest in the morning on the P Zero White medium tyre, and Lewis Hamilton fastest in the afternoon on the P Zero Yellow soft.

This combination of tyres has been chosen to ensure plenty of pace and strategy options for all the cars, but the compounds will have to be managed carefully to unlock the most speed. With the accent on tyre strategy, obtaining the most comprehensive amount of track data possible from free practice was a priority - especially with the latest generation of cars that feature new hybrid power units and reduced aerodynamic downforce. There is a lap time difference of 1.8 to 2.0 seconds between the two compounds, which will be the key to the strategy.

Free practice followed the usual format, with all the cars using just the medium compound throughout the morning session. The drivers used the soft tyre for the first time during the afternoon session, as they carried out long runs on both compounds with different fuel loads, to assess relative levels of performance. Using this information, the optimal strategy can be calculated.

However, this does not take into account variable weather, which is a hallmark of Spa. Even cooler weather is possible over the rest of the weekend, with a chance of rain tomorrow.

Paul Hembery: "It's always a pleasure to be at Spa, which is one of the truly great race circuits of the world. This year, with reduced downforce, it has arguably become even more spectacular, with the cars sliding around more and drivers needing maximum bravery to take Eau Rouge flat-out. We experienced cool conditions today, which obviously had an effect on the performance of the tyres, but this looks set to remain for the rest of the weekend: perhaps with some rain on Saturday. Despite the cool temperatures, we experienced very little by way of graining, and there were no big surprises. We will now analyse all the data carefully, but from what we can see so far the tyres are behaving in exactly the way we would expect, and we are likely to see two pit stops during the race for most competitors."

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