Lewis Hamilton completed a clean sweep of practice sessions at the United States Grand Prix after topping the final hour before qualifying on Saturday morning in Austin.
The Mercedes driver, looking for his fourth world title at a circuit he has won at each of the last three years, lowered his own lap record with a 1:34.478s on Ultrasoft tyres but was joined at the top by championship rival Sebastian Vettel in second and less than a tenth off the pace as the German recovered from a troubled Friday.
Hamilton’s teammate Valtteri Bottas was able to win the battle of the Finns’ finishing ahead of Kimi Raikkonen as the duo claimed third and fourth places respectively.
Red Bull’s form dropped compared to Friday with lead driver Max Verstappen fifth but some 0.6s adrift of the top while Daniel Ricciardo was only a disappointing ninth.
More frustratingly for the Milton Keynes outfit, it was confirmed in the session new engine parts had been fitted to the Dutchman's car overnight meaning a 15-place grid penalty.
Felipe Massa snatched sixth for Williams, benefiting from the improving track conditions late in the session to move ahead of the Renault drivers as Nico Hulkenberg was just ahead of new teammate Carlos Sainz for the first time this weekend as they finished a respective seventh and eighth
Force India maintained their presence in the top 10 with Sergio Perez as the Mexican led teammate Esteban Ocon who missed out on the top 10 by less than two-tenths of a second.
Lance Stroll was ahead of the two McLarens in 12th as Fernando Alonso fell back from his seventh place in Practice 2 and was just one place in front of Stoffel Vandoorne as Brendon Hartley continued his respectable start to his first full F1 Grand Prix weekend with 15th for Toro Rosso.
Kevin Magnussen was only 16th as Haas’ home Grand Prix continued to disappoint while teammate Romain Grosjean saw his session end early as his car got stuck in the gravel, after losing control in the blustery wind at the exit of Turn 7.
The Frenchman's initial time left him 19th behind the two Saubers with Marcus Ericsson finishing ahead of teammate Pascal Wehrlein in 17th and 18th. The Swiss team will simply be hoping to fully benefit from grid penalties for four drivers as Hartley, Vandoorne and Hulkenberg join Verstappen in taking new engine components.
At the back was Daniil Kvyat as the returning Russian was only able to complete six laps before a throttle issue meant he had to sit out for the rest of the session.
