George Russell saw off Mercedes teammate Kimi Antonelli in first practice for the Spanish Grand Prix in Madrid.
Russell finished 0.286 seconds clear of Antonelli as Mercedes set the pace on Formula 1's return to the Spanish capital after a 45-year hiatus.
Charles Leclerc was third, with his Ferrari teammate Lewis Hamilton a place behind. Max Verstappen and Lando Norris finished fifth and sixth respectively.
Russell's world championship hopes were dealt a setback at the previous round in Monza after he saw title rival Antonelli win from 19th on the grid.
Antonelli is 66 points ahead of Russell with 10 rounds to go, starting here in Madrid for the first time since 1981. However, the Madring is a new street venue on the outskirts of the city.
A number of drivers feared the track, with its imposing concrete walls and high-speed corners, would lead to a series of accidents. Indeed, Russell described the track as the most "risky" on the calendar and Verstappen suggested it could be a "car killer."
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But the one-hour running passed without incident, albeit in front of swathes of empty seats in the sparsely-populated grandstands.
F1 chiefs will hope the number of spectators increases over the remainder of the weekend.
Back on track, Nico Hülkenberg described Hamilton as "nasty" after he felt the seven-time world champion blocked him at the final corner.
Hamilton is 76 points behind Antonelli in his fading bid for a record eighth world crown.
He finished 0.543 seconds behind Russell but set his best lap on the slower medium tyre and will expect to be quicker when he puts on the softs in the second running of the day.
Verstappen finished six-tenths back, with defending world champion Norris even further adrift, some nine-tenths off the leading pace. The second session starts at 4 p.m. BST.