Max Verstappen set the early pace, pipping Valtteri Bottas in Practice at the Abu Dhabi Grand Prix.
With the daytime conditions unrepresentative of what drivers will face in qualifying and the race, the action was quite subdued at Yas Marina.
But that didn't stop Verstappen bolting on a set of softs and posting a 1m37.378s, to finish 0.034s ahead of the Mercedes on the same tyre.
Last week's podium scorer Esteban Ocon was third in the Renault, as a spin for Alex Albon compromised his soft tyre run, leaving the Red Bull in fourth.
It was a problematic start for Lewis Hamilton upon his return from missing the Sakhir GP due to Covid-19, as a sticking brake cost him around 40 minutes of running.
Mechanics, including half of Bottas', helped repair the issue on his Mercedes, before the world champion would complete the rest of his session on a single set of hard tyres, eventually finishing fifth.
Heading into FP1, many eyes were on Mick Schumacher, as the newly-crowned F2 champion participated in his first practice session.
And the German was solid enough in the Haas, albeit only 18th and almost four seconds off the pace. But that was irrelevant as the Schumacher name returned to F1 for the first time since 2012.
Racing Point made a solid start to the weekend with Lance Stroll sixth and Sergio Perez seventh.
However, for the Mexican, who heads into his final race at the team fresh from claiming his first F1 win in Bahrain, a new engine will force Perez to start from the back of the grid.
AlphaTauri also continued their strong pace with both cars inside the top 10, while Kimi Raikkonen was 10th.
McLaren and Ferrari filled positions 11-14, ahead of Robert Kubica in 15th, as the Pole made another FP1 appearance at Alfa Romeo.
Back at Williams, George Russell was back down the field in 16th, ahead of Latifi, Schumacher and Pietro Fittipaldi, who again replaces Romain Grosjean in the second Haas.
Daniel Ricciardo brought up the field as a fuel pressure issue forced him to pull off the track without setting a time in the Renault.
Full results from Practice 1 can be seen below:
