Leclerc tops extended Miami FP1 as Mercedes grapples with engine issues

Key facts

• Charles Leclerc fastest in FP1 with 1m29.310s, 0.297s ahead of Max Verstappen.
• Practice extended to 90 minutes due to five-week break and Sprint format.
• Ten of 11 teams introduced upgrades; Aston Martin only team without declared developments.
• Mercedes' Kimi Antonelli did not run on soft tyres due to engine investigation.
• George Russell suffered turbo issues and flat-spotted both front tyres.
• Aston Martin delayed 25 minutes by power issue; Alonso and Stroll finished 19th and 22nd.
• Oscar Piastri third fastest, Lando Norris seventh after aborting a lap.
• Sprint qualifying later Friday sets grid for Saturday's sprint race.

Leclerc leads the field in Miami's sole practice

Charles Leclerc topped the timesheets in Friday's only practice session for the Miami Grand Prix, posting a lap of 1 minute 29.310 seconds at the Miami International Autodrome. The Ferrari driver edged Red Bull's Max Verstappen by 0.297 seconds and McLaren's Oscar Piastri by 0.448 seconds, as the Formula 1 season resumed after a five-week April break. The session was extended from the usual 60 minutes to 90, a change driven by the extended gap in the calendar, recent rule refinements to engine-management systems, and the Sprint format that compresses the weekend into a single practice session. Teams used the additional time to evaluate upgrades and re-acclimatise drivers to the 5.412-kilometre Florida circuit under hot and humid conditions.

Mercedes struggles with reliability issues

Mercedes, winners of the first three races of the season, endured a troubled session. Championship leader Kimi Antonelli, who had topped the times after half an hour, was forced to step out of his car before the final soft-tyre runs as the team investigated a power unit problem. He finished fifth overall, 0.769 seconds off the pace. George Russell, sixth fastest and 0.790 seconds behind Leclerc, reported a turbo making "a lot of noises… a bit like a steam train" early in the session. The issue was resolved with a reset in the garage, but Russell later suffered a massive double lock-up that flat-spotted both front tyres, hampering his running.

Ten teams bring upgrades; Aston Martin hobbled by power failure

Ten of the 11 teams declared aerodynamic or performance upgrades for Miami, with Aston Martin the only squad not introducing any developments. The team's running was delayed by a power issue in the garage that caused monitors and telemetry to fail; Fernando Alonso and Lance Stroll only turned their first laps 25 minutes into the session. They finished 19th and 22nd respectively, the latter 3.649 seconds off the lead. Ferrari debuted an updated version of their 'flip-flop' rear wing, while Red Bull deployed a rotating concept of their own, both seeking to close the gap to Mercedes. McLaren introduced numerous performance upgrades and showed encouraging pace: Piastri third, Norris seventh despite aborting a lap to avoid Alex Albon's Williams at the hairpin.

Alpine leads midfield; backmarkers struggle

Alpine's Pierre Gasly was eighth fastest, 1.277 seconds off Leclerc, with team-mate Franco Colapinto 11th. Carlos Sainz completed the top ten for Williams, 1.620 seconds behind, while Alex Albon was 12th, separated by under a tenth. The midfield pack included Haas's Ollie Bearman (13th) and Esteban Ocon (16th), with the two Audis of Gabriel Bortoleto (14th) and Nico Hulkenberg (15th) between them. Racing Bulls, Cadillac and Aston Martin formed the backmarkers. Liam Lawson was the fastest of the six drivers from those teams, 17th overall, setting his best time on medium tyres. Sergio Perez finished 18th for Cadillac, and Valtteri Bottas 20th, while Arvid Lindblad was 21st for Racing Bulls.

Sprint qualifying looms as teams assess upgrades

With only one practice session before the weekend's competitive action, teams now face a compressed schedule. Sprint qualifying is scheduled for 16:30 local time (21:30 BST) on Friday, setting the grid for Saturday's sprint race. The extended practice gave drivers and engineers a chance to understand the implications of the rule changes to engine-management systems, which have been a focus of development. Leclerc's benchmark on soft tyres came on his second push lap, having already been fastest on hard tyres with a 1m29.855s. Verstappen looked more assured than Red Bull team-mate Isack Hadjar, who was ninth, 1.563 seconds off the lead. The session was otherwise uneventful apart from several drivers running wide at the end of long straights as they explored braking points, and Piastri's minor brush with the wall in the closing minutes.

Outlook: Ferrari's form signals a tight battle ahead

Ferrari's strong showing in practice suggests they could challenge Mercedes' early-season dominance, though the true pecking order will only emerge in qualifying and the sprint. Leclerc's pace on both hard and soft compounds indicates a well-balanced car, while Hamilton's fourth-place finish, 0.467 seconds off his team-mate, shows the team's depth. Mercedes' reliability issues, though resolved for now, raise questions about their ability to sustain their winning streak. The extended break and rule changes have reshuffled the competitive order, and the Miami weekend will provide the first clear indication of which teams have best adapted. With only one practice session, any missteps in setup or strategy could prove costly.

The bottom line

• Charles Leclerc leads FP1, but the gap to Verstappen and Piastri is small; Ferrari's upgrades appear effective.
• Mercedes faces reliability concerns with both cars, potentially compromising their sprint and race pace.
• Ten teams introduced upgrades, making Miami a key development benchmark for the 2026 season.
• Aston Martin's lack of upgrades and power issue leaves them at the back, three seconds off the pace.
• Sprint qualifying later Friday will provide the first competitive order after the five-week break.
• The extended 90-minute practice was crucial for teams to adapt to rule changes and new parts.