Valtteri Bottas topped the second and final day of Formula 1's first in-season test of the year in Bahrain for Mercedes, finishing almost three-tenths of a second clear of Ferrari's Sebastian Vettel.

Bottas returned to the wheel of the Mercedes W08 on Wednesday three days after failing to convert his maiden F1 pole into a breakthrough victory, finishing the Bahrain Grand Prix in third place.

Bottas managed to complete more mileage than any other driver at the Bahrain International Circuit, turning in 143 laps with a best lap of 1:31.280.

The Finn finished the day at the top of the timesheets, with Vettel finishing 0.294 seconds shy after missing most of the morning session due to an issue on his car.

Vettel managed to rack up 55 laps in the afternoon en route to second place in the standings, with Toro Rosso driver Carlos Sainz Jr. finishing a further three-tenths of a second behind in third place.

Stoffel Vandoorne made up for McLaren's miserable Tuesday to complete 81 laps in total, finishing with the fourth-fastest time. The team left Bahrain with just 98 laps to its name, though, a figure much lower than its rivals.

Kevin Magnussen finished fifth for Haas ahead of Force India's Esteban Ocon, who handed the VJM10 car over to team-mate Sergio Perez for the afternoon. Perez propped up the timesheets in P12, 3.7 seconds off Bottas' fastest time.

Daniil Kvyat wound up seventh for Toro Rosso, having split running with Sainz, while Gary Paffett ended the day eighth for Williams as he made his first appearance in an F1 car since 2013, completing 126 laps.

Sergey Sirotkin's first full day in the Renault R.S.17 car saw him finish ninth with 90 laps to his name, while Pierre Gasly was P10 for Red Bull. Sauber's Pascal Wehrlein finished up 11th, chalking up another 91 laps as his push for full fitness continued.

Teams will now be restricted to running on grand prix weekends only until the next in-season test, due to take place following the Hungarian Grand Prix.

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