It was a familiar sight at the top of the timesheets for Formula 1's for practice session of 2017, with the Silver Arrows first and second.
Mercedes' Lewis Hamilton led the field with a 1'24.220 on ultra-soft tyres which was five-and-a-half seconds quicker than in the same session last year.
The Brit left team mate Valtteri Bottas at a reasonable distance, 0.583s behind, with Red Bull Racing pair Daniel Ricciardo and Max Verstappen following at respectively 0.666s and 1.026s although the Milton Keynes cars were shod on the super-soft rubber.
Ferrari appeared to leave its pre-season momentum in the garage, with Kimi Raikkonen setting his best time on the super-soft compound but 1.152s off Mercedes' pace reference and leading team mate Sebastian Vettel by a tenth of a second. Like Red Bull, Ferrari also stayed off Pirelli's ultra-soft tyre.
The German concluded FP1 earlier than scheduled, heading back to the Scuderia's garage ten minutes before the end of the session with a suspected MGU-K problem on his SF70H.
Williams' Lance Stroll was the first man out on the track, topping the timesheets on his first flying lap on a Grand prix weekend. The Canadian acquitted himself well, and avoided blotting his copy book with a fastest lap that put him 13th overall.
Renault's Jonathan Palmer was a victim early on of a seal fault issue while McLaren's Stoffel Vandooren struggled behind the wheel of a recalcitrant McLaren, the pair closing out the timesheets respectively 4.365 and 4.475 off the leader's pace.
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