McLaren driver Lando Norris set the fastest time during first practice at a windy Zandvoort, during a limited spell of dry running.
Heavy rain fell during the build-up to the one-hour session, with several drivers staying in the garages, while strong gales buffeted the circuit throughout running.
The track surface dried sufficiently for slick tyres to be run for the final 10 minutes of the session, with the circuit becoming busier after the initial quiet spell.
Norris moved to the front as conditions improved before World Champion Max Verstappen vaulted to the front.
But Norris reasserted his authority with a time of 1:12.322, on Soft tyres, to finish 0.201s ahead of Verstappen, who has won all of the grands prix held at Zandvoort since the event’s revival in 2021.
McLaren, which trails Red Bull by 42 points in the Constructors’ Championship, is introducing the biggest raft of updates since its transformative Miami package.
Mercedes’ Lewis Hamilton was third-best though his prospects of challenging for top spot were thwarted when he encountered traffic through the final sector.
Ferrari’s Carlos Sainz was the fastest Medium-shod runner in fourth place, ahead of Mercedes’ George Russell, and Williams’ Alex Albon.
Williams has introduced its largest upgrade package of the campaign, partly targeted at reducing the FW46’s weight, though the car still remains slightly above the minimum limit.
Oscar Piastri was seventh for McLaren, ahead of Haas pair Nico Hulkenberg and Kevin Magnussen, with Sauber’s Zhou Guanyu rounding out the top 10.
Ferrari test driver Robert Shwartzman had his first FP1 outing of the campaign for Sauber, in place of Valtteri Bottas, and finished in 16th position.
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