Lewis Hamilton in the pits during Friday practice at Austin. (Photo: AFP/Mark Ralston) |
The 34-year-old Mercedes driver, revelling in the return of his regular race engineer Peter 'Bono' Bonnington, clocked a best lap in one minute 33.232 to outpace nearest rival Charles Leclerc of Ferrari by three-tenths of a second.
Having spent the morning's opening session working on set-up variations, Hamilton proved he was back on form with a succession of quick laps in his race simulation run to give himself a great chance of claiming the 2019 title with a sixth victory in eight races at the Circuit of the Americas.
Hamilton needs only to finish in the top eight to be champion even if team-mate Valtteri Bottas wins the race.
If Bottas fails to win, Hamilton will take the title.
Max Verstappen, frustrated in Mexico last weekend, but quickest in opening practice in Austin, was third for Red Bull ahead of Sebastian Vettel in the second Ferrari, Bottas and Alex Albon in the second Red Bull.
Pierre Gasly was sixth for Toro Rosso ahead of McLaren's Carlos Sainz, Lance Stroll of Racing Point and Antonio Giovinazzi for Alfa Romeo.
After the chill of opening practice in the morning, the second session began in milder conditions following an interval dominated by complaints about the bumpy circuit surface, particularly at Turn One.
Albon was quickest early on in the session followed by Sainz, Bottas and then Leclerc with Hamilton rising to second, one-tenth behind the Monegasque, as he began his pursuit of a strong weekend's work and a sixth title in earnest.
There was an early red flag to halt the action briefly after 14 minutes when Grosjean lost control of his Haas and hit the barriers at Turn Six. On resumption, Antonio Giovinazzi survived a spin at the same corner.
In more favourable conditions, at 16 degrees Celsius, the lap times began to tumble with Vettel finding a groove to top Bottas before Leclerc took over followed by Hamilton, a five-time winner at the Texas track, who was clearly back on top of his set-up after a muddled morning.
As the teams began their race simulation runs, the champion-elect said: "It's getting colder out here."
And then he embarked on a series of laps, before being warned by Bonnington that he needed to be careful of track limits at Turn 19.
"We've had two laps with warnings already," said the engineer.
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