Mercedes’ Lewis Hamilton set the pace in a wet/dry opening practice session for the United States Grand Prix as he beat title rival Sebastian Vettel of Ferrari by more than half a second at the Circuit of the Americas.

Championship leader Hamilton set a best time of 1:36.335s on the supersoft Pirelli compound tyres to finish 0.593 seconds clear of Vettel. Hamilton’s team-mate Valtteri Bottas took third place five hundredths of a second further back.

The session began in damp conditions after early morning abated shortly before the green light was shown at the put exit.

That led to the early running being conducted on the Pirelli’s intermediate tyres and it was Hamilton who initially led the way on the green-banded compound. He was usurped by Red Bull Racing’s Max Verstappen. Prior to the session it had been announced that the Dutchman has inked a new three-year deal with the Milton Keynes squad.

As the track began to improve, it was Williams’ Felipe Massa who found the sweet spot with the intermediates and the Brazilian was fastest in the early phase. Thje crossover point had been reached, however, and Vettel was soon out on supersoft Pirelli tyre. He swiftly claimed top spot on the timesheet with a lap of 1:45.960s.

The track was now improving rapidly and the time began to tumble. After Ricciardo has lowered the benchmark, Hamilton went significantly quicker to claim P1 in

1:39.266s on supersoft tyres. The Championship leader then improved with a lap of 1:36.335 that stood until the end of the session.

Behind the top three, Verstappen took fourth spot with a lap of 1:37.339 to stand just over a second off the pace. Stoffel Vandoorne made a good start to the weekend with Mclaren by taking fifth spot a little over a hundredth of a second behind Verstappen, though the Belgian’s time was set on ultrasofts tyres.

Vandoorne’s team-mate Fernando Alonso, fresh from signing a new multi-year deal with McLaren, had a less enjoyable session, however. The Spaniard spent the bulk of the session in the garage as his team worked to fix a hydraulic leak. He completed just four laps.

After his early exploits on intermediates Massa finished sixth for Williams in sixth, while Kimi Räikkönen was seventh in the second Ferrari.

Force India's Esteban Ocon was eighth ahead of team-mate Sergio Pérez, while Carlos Sainz, making his first appearance for Renault after switching to the French manufacturer from Toro Rosso was tenth. The Spaniard was eight tenths of a second ahead of team-mate Nico Hulkenberg who ended the session in 13th place.

Driving in place of Sainz at Toro Rosso at this race is New Zealander Brendon Hartley. The 2015 WEC champion and 2017 Le Mans 24 Hours winner made his F1 weekend debut by finishing in 14th place with a lap of 1:39.267. Hartley was 1.1s quicker than Seal Gelael in the other Toro Rosso. Gelael was driving in place of Daniil Kvyat who is set to return to race action for the Italian team this weekend after two races out.

2017 United States Grand Prix – Free Practice 1
1 Lewis Hamilton Mercedes 18 1:36.335
2 Sebastian Vettel Ferrari 20 1:36.928 0.593
3 Valtteri Bottas Mercedes 10 1:36.979 0.644
4 Max Verstappen Red Bull 21 1:37.339 1.004
5 Stoffel Vandoorne McLaren 26 1:37.352 1.017
6 Felipe Massa Williams 23 1:37.570 1.235
7 Kimi Raikkonen Ferrari 20 1:37.598 1.263
8 Esteban Ocon Force India 25 1:37.808 1.473
9 Sergio Perez Force India 20 1:37.861 1.526
10 Carlos Sainz Jr. Renault 24 1:38.093 1.758
11 Kevin Magnussen Haas 16 1:38.408 2.073
12 Lance Stroll Williams 25 1:38.534 2.199
13 Nico Hulkenberg Renault 19 1:38.904 2.569
14 Brendon Hartley Toro Rosso 28 1:39.267 2.932
15 Romain Grosjean Haas 17 1:39.336 3.001
16 Daniel Ricciardo Red Bull 14 1:39.366 3.031
17 Sean Gelael Toro Rosso 25 1:40.406 4.071
18 Marcus Ericsson Sauber 19 1:40.448 4.113
19 Charles Leclerc Sauber 25 1:40.828 4.493
20 Fernando Alonso McLaren 4

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