The sky was looking a touch darker in Austin but there was no real threat during the final practice session of the premier class and it allowed Jack Miller to cruise into the lead of another session, this time with a one tenth advantage on his rivals. Adding to a pretty low key Friday at CotA, Joan Mir made a fiery start in FP4, as his engine spat out flames down the back straight, but the frustration proved to be solid motivation, as he rejoined on his second machine and climbed into second position. Pecco Bagnaia progressed to join his teammate in the top three, ahead of the initial leader of the session, Johann Zarco, whose recovery from arm pump surgery seems to be going to plan.
Fabio Quartararo, Takaaki Nakagami and Alex Rins also finished within half a second of the leader, while Marc Marquez had quite a few off track excursions on his way to eighth place. Miguel Oliveira was the lead KTM, posting an identical time to Aleix Espargaro. The Aprilia man was a new addition to the top 10 in Texas, after not looking as great in the rest of the practice sessions, but his session ended prematurely after losing the front on an infamous bump at turn two. The Avintia duo of Luca Marini and Enea Bastianini were over three tenths slower than Espargaro and one full second behind the leader. Speaking of Espargaros, the Repsol Honda variety had a tumble early on at turn 12 and dropped to 17th.