Vettel managed to set two consecutive fastest laps at the start of the afternoon session with his final benchmark being a 1m19.673s, which was set on the soft tyres.
Defending champion Lewis Hamilton is due to take over testing duties from Bottas for Mercedes on Tuesday afternoon.
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The game marked the 130th time that Messi has scored at home in La Liga - of those, Barcelona have lost only twice. Barcelona shook off conceding in the first two minutes, to defeat Girona 6-1 at the Nou Camp on Saturday night.
"With the weather conditions being up and down, and the loss of track time we had yesterday, it made sense to keep Valtteri in the vehicle this afternoon", said the Briton in a team review of the day's action. "It is handling good so far". You can always improve it but in terms of lap times we are doing well, so we don't really have big issues.
"Last year I did not perform on the level I should have and I learned a lot from that".
McLaren's Stoffel Vandoorne was third fastest on the day, just 0.001secs quicker than Verstappen, but the Belgian was using the fastest hyper-soft tyre, which is three grades softer than the soft used by Vettel, so the time can not be directly compared. The auto spent most of the afternoon in the garage after the engine cover showed tell-tale signs of overheating around the exhaust.
McLaren's Stoffel Vandoorne was just five hundredths of a second behind on an encouraging morning for the British team at the Circuit de Catalunya.
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The circuit opened for business shortly before midday, but it took a few more hours before the teams completed any significant running due to the high risk of damage to their cars. He lost it at Turn One, while Sauber's Charles Leclerc and Haas' Kevin Magnussen also had spins. "I don't think I've ever driven in such cold conditions before in Formula 1". I think like this it works well. I don't know yet but in terms of general operation it's been very smooth so it's good to come here, switch on the auto and be able to run.
In contrast to Hamilton's limited running, Bottas has already racked up 152 laps of testing, the equivalent of two and a half race distances, after he was given an entire day behind the wheel on Tuesday.
Although early test runs aren't the be all and end all, Red Bull's new vehicle looks to be pretty fast. Toro Rosso will also be pleased with the 82 laps completed by Pierre Gasly, marking another day of Honda not being bad (a surprise, I know).
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They may be troubled by a couple of extra injuries, and they don't have much to play with defensively. We are taking steps forward with a lot of young players.