Mercedes dominate but Alonso in Silverstone practice top 10
Bottas and Hamilton finished the first practice for the British Grand Prix ahead of Red Bull and Ferrari, while the Spaniard makes some progress.
Valtteri Bottas topped the times ahead of his Mercedes team-mate Lewis Hamilton in Friday morning's opening free practice session for this weekend's British Grand Prix.
Mercedes, Red Bull, Ferrari
The Finn clocked a best lap of one minute and 29.942 seconds to outpace the three-time champion by 0.078sec.
Max Verstappen was third for Red Bull ahead of his team-mate Daniel Ricciardo and the two Ferraris, with Kimi Raikkonen taking fifth and world championship leader Sebastian Vettel sixth.
Alonso's McLaren in chasing pack
Daniil Kvyat was seventh for Toro Rosso ahead of two-time champion Fernando Alonso who was an encouraging eighth for the struggling McLaren team. Felipe Massa was ninth for Williams and Stoffel Vandoorne 10th in the second McLaren, suggesting the team's new Honda power unit has the performance to deliver improvement.
On a cool, grey and overcast day at the former wartime aerodrome in central England, Bottas stamped his authority on proceedings from the early stages while Hamilton struggled to match his fastest laps.
New pole lap record at Silverstone
It was not long before the 2016 pole lap time was beaten, sure evidence of the speed of this year's new era fatter and faster cars on one of the quickest circuits.
On a track which was expected to favour Mercedes' longer wheel-base car and powerful engine, Bottas remained three-tenths clear of Hamilton with both Ferrari and Red Bull working their way into contention.
In the chilly conditions, Vettel smacked the kerbs at the exit of Village corner as Verstappen, with some flamboyance, climbed to third before the final minutes of action.