Marc Marquez set the pace on the first day of practice for the Grand Prix of the Americas despite a crash in Friday's second session.
MotoGP championship leader Marquez, who topped the timesheets in FP1, continued to dominate in FP2 and was fastest in the session by lap six.
It appeared as though the Spaniard would fall below two minutes and four seconds, but he lost the front of his Repsol Honda at Turn 20 and walked back to the pit lane unharmed.
Marquez later returned to the track and set the fastest lap of the day with a time of 2:04.034.
That was a huge 0.706secs faster that Ducati's Andrea Iannone - who has a three-place grid penalty in Austin - while Maverick Vinales (Suzuki) completed the top three.
Movistar Yamaha duo Jorge Lorenzo and Valentino Rossi were fifth and sixth in FP2, while Dani Pedrosa was more than a second off team-mate Marquez in eighth.
In FP1, Marquez's time of 2:04.953 was enough to lead the way, with Lorenzo 0.255secs adrift in second, while Iannone was third fastest.