Mercedes's Lewis Hamilton continued to dominate the timesheets in practice for Sunday’s United States Grand Prix, with the Briton, who could wrap up a fifth title this weekend, running a second clear of Toro Rosso’s Pierre Gasly in a badly rain-disrupted second session at the Circuit of the Americas.

Meanwhile, the fading title hopes of Hamilton’s sole title rival, Sebastian Vettel, were dealt a blow when he was hit with a three-place grid penalty for a rules infringement in the morning practice session.

Vettel failed to stay above the minimum time set by the FIA during a red flag period in FP1 caused by an incident involving Sauber’s Charles Leclerc.

The stewards ruling on the matter stated: “Art. 31.6 was added this year to ensure that drivers reduce speed significantly during a red flag. Breach of this regulation is seen to be an extremely serious matter.”

In FP2, there was no running in the first half of the session as heavy rain made conditions treacherous, but eventually the downpour eased off drivers began to emerge from the pit lane and in a somewhat disjointed final half hour Hamilton claimed top spot with a time of 1:48.716 set in the final five minutes of the session. The championship leader only completed three laps in the entire session.

Second spot on the timesheet was taken by Toro Rosso’s Pierre Gasly. The Frenchman posted 10 laps of COTA during the session and ended the session 1.012s behind Hamilton with a best time of 1:49.728. Red Bull Racing’s Max Verstappen was third with a time seventh hundredths of a second slower than his 2019 team-mate Gasly.

Fourth place went to Fernando Alonso, with the McLaren driver finishing ahead of Renault’s Nico Hulkenberg and the second Toro Rosso of Brendon Hartley.

Marcus Ericsson was seventh for Sauber ahead of the second McLaren of Stoffel Vandoorne, and then came the Ferraris, with Kimi Räikkönen ninth and Vettel tenth. In an unrepresentative session Räikkönen was 4.7s off the pace, while Vettel finished over 5 seconds off Hamilton’s pace.

2018 Formula 1 United States Grand Prix – Free Practice 2
1 Lewis Hamilton Mercedes 3 1:48.716
2 Pierre Gasly Toro Rosso 10 1:49.728 1.012
3 Max Verstappen Red Bull Racing 5 1:49.798 1.082
4 Fernando Alonso McLaren 3 1:51.728 3.012
5 Nico Hulkenberg Renault 6 1:52.208 3.492
6 Brendon Hartley Toro Rosso 19 1:52.505 3.789
7 Marcus Ericsson Sauber 9 1:53.070 4.354
8 Stoffel Vandoorne McLaren 10 1:53.354 4.638
9 Kimi Raikkonen Ferrari 7 1:53.443 4.727
10 Sebastian Vettel Ferrari 8 1:53.912 5.196
11 Charles Leclerc Sauber 9 1:54.101 5.385
12 Lance Stroll Williams 5 1:54.637 5.921
13 Sergio Perez Racing Point Force India 6 1:54.963 6.247
14 Esteban Ocon Racing Point Force India 6 1:55.348 6.632
15 Sergey Sirotkin Williams 8 1:55.446 6.730
16 Carlos Sainz Renault 2