Double world-MotoGP-champion Marc Marquez set the fastest time in a free practice ahead of the Grand Prix of the Americas in Austin, Texas on Friday.
The 22-year-old completed his best lap in less than two minutes and five seconds in the second free practice session, which took place on a dry track in sunny conditions.
Marquez said he is confident going into Sunday's race.
"Well, of course, two different sessions, but we're positive because Sunday we don't know yet which weather we will have, so we ride on rain and it was good, the feeling was good, of course on rain conditions there is always a question mark because you never know, but on dry conditions I feel well."
Marquez was about three-tenths of a second quicker than Britain's Cal Crutchlow, who is riding with a new chassis and seat set-up.
Italy's Andrea Iannone finished third.
