Bottas' benchmark from FP1 was toppled around 15 minutes into the afternoon session at Silverstone, as Hamilton posted a 1m28.780s on soft tyres before quickly improving to a 1m28.543s.

That put Hamilton a full six tenths clear of the field, led by Ferrari's Kimi Raikkonen, until Bottas switched from mediums to supersofts at the 30-minute mark and set a new best of 1m28.496s.

Hamilton likewise equipped the red-marked rubber, but ran off the track at Chapel and told his engineers he feared he had damaged the car in the process.

With teams shifting their focus towards longer runs for the latter half of the session, Bottas' best effort stood as the quickest time of the day, 0.047s clear of Hamilton's best time on softs.

Raikkonen was third-quickest, going 0.338s slower than compatriot Bottas on his supersoft run and 0.128 faster than the second Ferrari of Sebastian Vettel.

There was late drama for Raikkonen, however, when the Finn suffered a moment of snap oversteer at Becketts and spun into the gravel, although he got going again without outside assistance.

Max Verstappen was best of the Red Bull drivers in fifth, 0.602s off the pace on supersofts, while teammate Daniel Ricciardo was sixth, nearly half a second down on the Dutch driver on the same tyre.

Nico Hulkenberg, Felipe Massa, Fernando Alonso and Esteban Ocon completed the top 10, all using supersofts, with Williams driver Massa spinning at Chapel late in the session after setting his best time.

The Brazilian also attracted the attention of the stewards for impeding Verstappen, Massa having passed the Red Bull driver around the outside at Club while both drivers were on long runs.

Carlos Sainz had a major off-track excursion at the Maggotts/Becketts complex at the very start of the session, which consigned the Toro Rosso driver to the pits until the final 40 minutes of the session.

He set the 11th-quickest time, ahead of teammate Daniil Kvyat in 12th.

Renault's Jolyon Palmer also had a spin at Brooklands, ending up 18th ahead of only the two Saubers.

Practice results:

Pos.	Driver	Chassis	Engine	Laps	Time	Gap
1	Valtteri Bottas	Mercedes	Mercedes	31	1'28.496
2	Lewis Hamilton	Mercedes	Mercedes	35	1'28.543	0.047
3	Kimi Raikkonen	Ferrari	Ferrari	36	1'28.828	0.332
4	Sebastian Vettel	Ferrari	Ferrari	36	1'28.956	0.460
5	Max Verstappen	Red Bull	TAG	32	1'29.098	0.602
6	Daniel Ricciardo	Red Bull	TAG	35	1'29.586	1.090
7	Nico Hulkenberg	Renault	Renault	37	1'29.936	1.440
8	Felipe Massa	Williams	Mercedes	36	1'30.006	1.510
9	Fernando Alonso	McLaren	Honda	28	1'30.238	1.742
10	Esteban Ocon	Force India	Mercedes	42	1'30.383	1.887
11	Carlos Sainz Jr.	Toro Rosso	Renault	26	1'30.555	2.059
12	Daniil Kvyat	Toro Rosso	Renault	34	1'30.562	2.066
13	Sergio Perez	Force India	Mercedes	43	1'30.624	2.128
14	Romain Grosjean	Haas	Ferrari	33	1'30.661	2.165
15	Lance Stroll	Williams	Mercedes	37	1'30.695	2.199
16	Stoffel Vandoorne	McLaren	Honda	31	1'30.782	2.286
17	Kevin Magnussen	Haas	Ferrari	33	1'30.835	2.339
18	Jolyon Palmer	Renault	Renault	25	1'30.879	2.383
19	Marcus Ericsson	Sauber	Ferrari	27	1'31.616	3.120
20	Pascal Wehrlein	Sauber	Ferrari	30	1'31.929	3.433