Mercedes and Bottas ahead mid-day in Barcelona

Mercedes' Valtteri Bottas topped the timesheet before mid-day at the Circuit de Catalunya on the fourth and final day of Week 1 of pre-season testing.

After yesterday's frustrating wash-out which deprived everyone of crucial mileage, teams resumed their test respective programmes this morning, although track conditions remained damp despite rising temperatures.

Bottas was among the front runners all morning but the emergence of a dry line just before the session's half-way point prompted the Finn to shed his intermediate rubber and bolt on the medium compound tyres.

Ultimately, the Mercedes driver, with 58 laps under his belt, put in the fastest lap of the day with a 1:22.789s, but Renault's Nico Hulkenberg was hot on heels of the Finn.

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The session will run uninterrupted, with no lunch break, to compensate for yesterday's botched dat.

As the only drivers running on slick tyres, Bottas and Hulkenberg were comfortably ahead of the field although Red Bull's Max Vesrtappen and the smooth running Honda-powered Toro Rosso of Pierre Gasly had both previously paid a visit to the top of the timesheet.

The single red flag of the session was provided by Marcus Ericsson when he beached his Sauber at Turn 2.

Running for Ferrari, Sebastian Vettel was conspicuously absent among the front-runners, as the Scuderia driver focused on his specific programme rather than any search for performance.

It was a troubled session however for Sergio Perez however who was left stranded in the Force India garage for the bulk of the morning, achieving just 11 laps compared to Bottas' 60-lap session.

Timing at 13:11 local time

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