Ferrari driver Charles Leclerc pipped Red Bull's Max Verstappen to top first practice at Formula 1's United States Grand Prix in Austin.
Leclerc was just under a tenth faster than Verstappen in an upgraded Ferrari as he aims to deny the Dutchman and his in-form Red Bull team a hat-track of grand prix wins.
On a hot Circuit of the Americas, Ferrari hit the ground running as it trialled its latest, and understood to be the final, round of 2026 aero upgrades. The update package for Texas features revisions to the floor, bargeboard, sidepod and diffuser.
While impressive sounding on paper, the team was keen to play down expectations, calling it a minor improvement. Whatever the case, Leclerc and Lewis Hamilton quickly managed to get up to speed in the early running on the undulating 5.5km circuit, with Leclerc's 1m36.61s on medium tyres 0.074s off Hamilton's first personal best.
McLaren's Lando Norris was third ahead of Mercedes duo Kimi Antonelli and George Russell, who donned the slower hard compound for their opening runs and shipped four and five tenths respectively.
Feedback on balance issues permeated the airwaves at COTA, which typically is a tough circuit to get right due to its varied track layout and bumpy surface.
Max Verstappen, Red Bull Racing
Just after the halfway mark, Leclerc took seven tenths off his previous benchmark as he switched to the softest tyre compound. Mitigating early balance and steering rack woes, Verstappen shot up the timesheets to take second, 0.084s behind Leclerc's 1m36.052s lap.
Verstappen's Red Bull, which featured an additional update to its new front wing, looked particularly impressive through COTA's first sector and its fast and flowing Esses. A lap that would see the four-time world champion usurp Leclerc was scratched for track limits at COTA's penultimate corner.
After suffering a couple of snaps of oversteer, Norris took third 0.245s behind, ahead of Russell as the top four teams all appeared in the same ballpark based on FP1's limited sample size.
World champion-elect Antonelli settled for fifth ahead of Hamilton and Piastri. Gabriel Bortoleto led the midfield in the Audi, taking eighth-place and just under a second off the pace of the frontrunners. That was slightly quicker than Arvid Lindblad in the Racing Bulls car, which has been comfortably leading the battle for fifth in the constructors' championship.
Liam Lawson held off Haas driver Oliver Bearman to round out the top 10, while Aston Martin showed glimpses of improvement as Fernando Alonso and Lance Stroll took 12th and 13th. That put the pair ahead of Isack Hadjar in the second Red Bull, who lost his one-lap run due to exceeding track limits.
FP1 featured one rookie runner in Cadillac's Colton Herta, who took the reins of Sergio Perez's car on home soil. The former IndyCar star was handed additional Friday practice sessions as he aims to collect the last couple of missing FIA superlicence points, making up for a curtailed FP1 session in Italy.
Williams man Alex Albon was the only driver not to set a competitive lap, as his team opted to conduct aero testing to aid its 2027 development.
F1 United States GP results - FP1
Results to follow
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