Sebastian Vettel continued his domination at the United States Grand Prix on Saturday when he topped the times in the final free practice session.
As on Friday afternoon, he wound up fastest with some ease ahead of his nearest rival, and Red Bull team-mate, retirement-bound Mark Webber.
The newly crowned four times world champion clocked a best lap time of one minute and 36.733 seconds to outpace Webber by two-tenths of a second.
On a clear and mild morning at the Circuit of the Americas, there was no repeat of the foggy delays of Friday morning as the 26-year-old German went fastest on his first run after 22 minutes.
He stayed out in front for the remainder of the one hour session as he set about setting up his car for the afternoon qualifying session ahead of Sunday's race in which he is seeking a record eighth straight win.
Last year's winner Lewis Hamilton was third fastest for Mercedes ahead of Nico Hulkenberg of Sauber, Romain Grosjean of Lotus and Jenson Button of McLaren.
Hamilton's Mercedes team-mate Nico Rosberg was seventh ahead of Sergio Perez in the second McLaren, Valtteri Bottas of Williams and Adrian Sutil of Force India.
Two time champion Fernando Alonso of Ferrari struggled again and wound up 11th.