Ferrari's Charles Leclerc was fastest in sole practice for the Miami Grand Prix sprint weekend on Friday as nearly all teams tested heavily upgraded cars after more than a month without racing.
The Monegasque lapped the Hard Rock Stadium track with a best time of one minute and 29.310 seconds in bright sunshine and steamy heat.
Red Bull's four-time world champion Max Verstappen was second fastest, 0.297 off the pace, with last year's winner Oscar Piastri third for champions McLaren.
Ferrari's seven-time world champion Lewis Hamilton was fourth with Kimi Antonelli, the 19-year-old world championship leader for Mercedes, fifth and 0.769 seconds slower than Leclerc.
Charles Leclerc.
— Formula 1 (@F1) May 1, 2026
Fastest in FP1 💨#F1 #MiamiGP pic.twitter.com/2PyegyRKZP
The Italian had some power unit issues, however, and did not complete a soft tyre lap.
Friday's session was extended by half an hour from the usual 60 minutes to give teams more track time after rules revisions and due to the extended break brought about by April's races in Bahrain and Saudi Arabia being called off due to the Iran war.
Qualifying for the points-paying Saturday sprint followed later on Friday.
George Russell was sixth fastest for Mercedes, but also had an engine issue, with McLaren's reigning champion Lando Norris seventh.
French drivers Pierre Gasly and Isack Hadjar, with Alpine and Red Bull respectively, were eighth and ninth, with Carlos Sainz completing the top 10 for Williams.