Carlos Sainz set the early pace for Ferrari after setting a best time of 1:36.857s in the opening practice session at the Circuit of the Americas.
Max Verstappen was second fastest and just 0.224s off Sainz's best effort, having completed just 14 laps.
Lewis Hamilton was a further 0.475s back, having set his fastest lap time towards the end of the session on the Soft tyre.
The session was interrupted after just 15 minutes when F1 returnee Antonio Giovinazzi (in place of Kevin Magnussen at Haas) spun at Turn 6 and crashed into the Tecpro barrier.
Whilst he managed to get the Haas out and back to the pits, the team elected to end his session early after just four laps due to him overheating the clutch and his car requiring a gearbox change.
Robert Shwartzman was best of the rookies in the session, finishing 16th fastest, ahead of Alex Palou (McLaren), Theo Pourchaire (Alfa Romeo) and Logan Sergeant (Williams).
Result Free practice 1 - United States
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