Bottas puts Williams on top on final day of pre-season testing

Valtteri Bottas signed off the 2015 pre-season in style by going fastest for Williams on the final day of testing at Barcelona on Sunday.
The Finn hit the front early and was never deposed, as a qualifying simulation on Pirelli's supersoft tyre yielded a 1m 23.063s - which left him almost half a second clear of the chasing pack.
Sebastian Vettel was second fastest for Ferrari, while Sauber's Felipe Nasr was the last man to get within one second of Bottas's benchmark in third. Like Bottas, Vettel and Nasr set their best times in morning runs on the supersoft.
Toro Rosso's Max Verstappen improved several times in the afternoon, eventually slotting into fourth ahead of Red Bull's Daniel Ricciardo. The Australian also made gains in the afternoon, having missed much of the morning with an ERS problem.
McLaren's day was similarly disrupted by technical gremlins. Jenson Button was only able to get out for two untimed laps in the morning, as a sensor problem meant the Honda power unit had to be removed. The afternoon proved slightly more productive as Button slotted into eighth, although he managed just 30 laps in total. Nasr, by comparison, was the day's busiest driver with 159 laps.
Sergio Perez also broke past 100 laps in what was his first day in the delayed Force India VJM08, with the Mexican's best time - a 1m 25.113s - just enough to shade Nico Rosberg's Mercedes for sixth.
Rosberg nevertheless had the honour of setting the outright best time of the test, after recording a blistering 1m 22.792s on day two.
Lotus's Pastor Maldonado rounded out the timesheet in ninth, and also triggered the red flags when he hit the barriers at Turn 4. Verstappen and Ricciardo also caused stoppages when they came to a halt on circuit.
Teams now have just under two weeks for final preparations ahead of the season-opening 2015 Formula 1 Rolex Australian Grand Prix. Opening practice commences at 1230 local time on Friday, March 13.
For more pictures from Barcelona, see our testing gallery.
Unofficial Sunday testing times from Barcelona to follow...

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