Red Bull’s Max Verstappen headed the times in the first practice session at the Mexico City Grand Prix.
Verstappen was 0.095 seconds quicker than Williams’ Alex Albon in second, despite running the medium tyres rather than the softs of those behind him.
The world champion’s team-mate Sergio Perez, cheered on by his home fans, was third, ahead of McLaren’s Lando Norris.
Ferrari’s Charles Leclerc was fifth ahead of the second McLaren of Oscar Piastri.
Ferrari’s Carlos Sainz was seventh, ahead of Alpha Tauri’s Daniel Ricciardo, Alpine’s Esteban Ocon and Aston Martin’s Lance Stroll.
Mercedes driver Lewis Hamilton, fresh from being disqualified from second place at the United States Grand Prix last weekend, was only 11th fastest, a second off the pace.
The teams all had a set of Pirelli test tyres to try during the session, which meant reading into the times was even more difficult than usual in first practice.
Aston Martin’s Fernando Alonso spent the session assessing the new floor the team introduced to mixed results in Austin last weekend and ended up 16th.
This is the first race weekend since Japan at the end of September that is not being run to the sprint format, and the first session was much less hectic than it was in Qatar and Austin, as teams have three sessions to decide their set-ups for race and qualifying rather than only one.
And it was characterised by five teams taking the opportunity to use up one of their two mandatory young driver outings.
The fastest of them was Briton Oliver Bearman, a member of the Ferrari driver academy, impressed in the Haas with 15th fastest time, four places and 0.4secs behind race driver Nico Hulkenberg.
Bearman had a scary moment when he got the car on the kerbs at the Esses and had to rescue what could have been a crash, but set a faster time on the soft tyres on his next lap.
Frenchman Isack Hadjar in the Alpha Tauri was 17th, 1.4secs slower than Ricciardo, ahead of Alpine’s Jack Doohan and Dane Frederik Vesti in the Mercedes.
Frenchman Theo Pourchaire had a difficult time in the Alfa Romeo, with a succession of braking problems that meant he failed even to complete a flying lap before his session was brought to a premature close.