The Ferrari driver led the only 90-minute FP1 at Miami by 0.297 seconds from Max Verstappen, with Oscar Piastri third and Lewis Hamilton fourth.
Mercedes pair Andrea Kimi Antonelli and George Russell finished fifth and sixth, while Verstappen reported poor gearshifts despite Red Bull appearing more competitive with its upgraded car.
The extended session was added because revised regulations and new upgrades had to be assessed before sprint qualifying, after Formula 1 resumed in Miami following a five-week hiatus.
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