Valtteri Bottas led a comfortable Mercedes one-two in first practice for the United States Grand Prix at Austin’s Circuit of The Americas, almost a second ahead of Max Verstappen.

The Finn’s fastest time of 1m34.874s was 0.045s quicker than Lewis Hamilton’s best effort and a substantial 0.932s faster than Max Verstappen’s quickest lap.

Bottas’s lap was built on a particularly impressive second sector, comprising Turns 7 to 12 and the long back straight. He gained half a second on Verstappen through that sector alone, and his 0.2s advantage over Hamilton through the middle split was enough to offset slower times in over the balance of the track.

But the session-topping performance came at a price, with Mercedes confirming during the practice hour that Bottas was set for his sixth internal combustion engine — his third in four races — and will subsequently be penalized five places on the grid.

His is one of three confirmed Mercedes power unit-related penalties being served this weekend, with Sebastian Vettel and George Russell installing new internal combustion engines, turbochargers and MGU-H components that will see them sent to the back of the grid in qualifying order.

Ferrari teammates Charles Leclerc and Carlos Sainz were split by 0.2s in fourth and fifth respectively despite both appearing unhappy with the balance of the car. Leclerc spun off the track into the gravel at Turn 6 early in the hour, and Sainz complained of oversteer and ride height problems at high speed.

Pierre Gasly was sixth for AlphaTauri ahead of Sergio Perez in the second Red Bull Racing machine. The Mexican was 1.9s off the pace on the hard tire; his best time on softs, which would have put him 0.011s behind teammate Verstappen, was deleted for exceeding track limits.

Lando Norris was eighth for McLaren ahead of Alfa Romeo duo Antonio Giovinazzi and Kimi Raikkonen. George Russell and Esteban Ocon followed just outside the top 10, with Aston Martin teammates Lance Stroll and Sebastian Vettel finishing 13th and 14th.

Fernando Alonso was classified 15th after setting 12 laps, the fewest of the field, having stopped on track just three minutes into the session. The team instructed him to park his car in the run-off area of Turn 12 as a precaution — with fluid leaking from the Alpine as it sat waiting to be recovered, causing an eight-minute red flag — but he was able to rejoin with repairs in the final 15 minutes.

Daniel Ricciardo, kitted out in a black Dale Earnhardt black tribute helmet, was 16th for McLaren ahead of Nicholas Latifi and Yuki Tsunoda.

Mick Schumacher was 19th and almost 4s off the pace, his Haas unscathed by side-by-side contact with Sergio Perez at the end of the back straight late in the session, while Nikita Mazepin finished 3.7s further back in last.