Read on for the latest from the Circuit de Cataluyna as the drivers prepare for what will be a crucial weekend in the 2018 season.
When the virtual safety vehicle finished Bottas improved twice on a new set of soft tyres and got down to a 1m18.411s before another Turn 10 moment, this time locking up and running deep after encountering traffic. "Since the last race, I have not thought for one second that I am leading the world championship", the four-time world champion said ahead of tomorrow's Spanish Grand Prix. Hamilton lapped in 1:18.259, just ahead of the Red Bull pair of Daniel Ricciardo and Max Verstappen.
Mercedes also dominated the second session but this time it was Lewis Hamilton who topped the standings with a best time of 1:18.259, once again achieved on the soft compound tyres.
Ricciardo, who crashed with Verstappen in Azerbaijan, had a tough start to his weekend in Barcelona by hitting a tire barrier midway through the first session, losing a lot of track time.More news: Putin, Erdogan Agree Trump Was 'Wrong' on Iran Nuclear Deal
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Williams saw Robert Kubica on duty for his first of three FP1 sessions that he'll be enjoying this year, the Pole temporarily replacing Sergey Sirotkin. He participated in preseason testing this year.
Kubica, who had a spin toward the end of the session, finished with the second-to-last time - in front of teammate Lance Stroll. "I know there's been a lot of talk about this vehicle in Australia, but I think there's more than one development piece that wouldn't have been in Australia". That work pushed back the introduction of a number of new parts, but in Barcelona McLaren ran with a radically updated nose and bargeboard assembly, and Brown said that the early signs are encouraging.
It's hard to gauge where the drivers sit in the power rankings after the conditions played their part in Friday's practice, but the stakes will be a lot higher as qualifying gets underway on Saturday. "It sounds odd that you can be happy with P19, but actually I'm happy". Brendon Hartley and Grosjean among them. Bottas and Vettel also span but were able to continue their runs without significant damage.
Sergio Perez finished as the lead Force India in P13 ahead of Marcus Ericsson in the second Sauber, with Carlos Sainz Jr. taking 15th for Renault.