Ferrari topped the timing sheets in the only practice session for the United States Grand Prix, both Carlos Sainz and Charles Leclerc going a solid quarter of a second faster than their closest rivals.
Max Verstappen was closest to them, although his team-mate Sergio Perez could only go 16th fastest, behind the returning Liam Lawson in the VCARB previously driven by Daniel Ricciardo.
Lewis Hamilton and George Russell both spun at high speed during the session, but were saved from any costly contact with the wall by the large run-off areas at the track.
The Sauber of Zhou Guanyu exited the session early, coming into the pits and being taken apart after the Chinese driver complained of a loss of power while out on track.
Yes, sprint qualifying is due to take place later on Friday, with the championship protagonists battling it out for pole position. The session is due to start at 10:30pm BST.