Lewis Hamilton made a powerful statement of intent as the Formula 1 season finally got under way at the Austrian Grand Prix.
The world champion was fastest in both practice sessions at the Red Bull Ring, leading team-mate Valtteri Bottas.
Mercedes have repainted their cars black, a new livery reflecting support for anti-racism and diversity.
The season is starting four months late after coronavirus laid waste original plans and forced a complete re-think.
Beyond eight races in Europe scheduled over the next 10 weekends, the shape of the rest of the season remains in flux, as a result of the differing impact of coronavirus around the world.
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To restart the championship, F1 has taken a series of measures to minimise the risks with coronavirus, with social-distancing protocols and a testing programme.
And the sport is making efforts to promote diversity as a result of the increased profile of the fight against racism following the global protests that were precipitated by the death of African-American man George Floyd in police custody in May.
Who's looking strongest?
The drivers are expected to make a public statement of their support for the anti-racism and diversity cause before the start of the race on Sunday.
On track, the colour scheme of the Mercedes might have changed from the silver that was first introduced in the 1930s but their domination of the sport looks set to continue.
They travelled to Austria for the first of two races on the compact but challenging track in the Styrian mountains as favourites, but the extent of their advantage on this first day of competitive action will be an unwelcome surprise to the rest of the field.
Red Bull's Max Verstappen was the third fastest car in the first session, 0.602secs off Hamilton, and Ferrari's Sebastian Vettel was fourth in the second session, 0.657secs off the Briton.
Mercedes appeared to be a good half-second clear of any other car on the evidence of the day, although Verstappen said he had broken his front wing on his fastest lap, which means there should be more potential in the Red Bull.
"It was great to be back," said Hamilton. "It's been a long time coming. It felt great to feel the new car.
"It's definitely looking good but you can never take too much from practice. The other teams may be down or up on power mode or fuel or whatever it may be. So we will take it with a punch of salt and try and see if we can improve the car tonight."
Third in the second session was Racing Point's Sergio Perez, in a car that has been dubbed the 'Pink Mercedes' or 'Tracing Point' because of its likeness to the 2019 title-winning car, which Racing Point admit they have copied.
Other teams have said they may protest the Racing Point on these grounds but Renault team boss Cyril Abiteboul said on Friday that his "priority" was to focus on the racing this weekend.
Mercedes are also facing questions over the legality of their car, after Red Bull lodged an official protest against their controversial dual-axis steering system (DAS). This changes the 'toe' angle of the front wheels for tyre wear and aerodynamic benefit.
Mercedes' traditional rivals struggled on this first day back on track.
Red Bull appeared to be suffering from a lack of rear stability, with both drivers complaining of oversteer.
Verstappen had two spins while team-mate Alexander Albon had one, providing an echo of pre-season testing, when they denied the car had an aerodynamic problem despite a number of spins for both drivers.
Verstappen could manage only ninth fastest in the second session, with Renault's Daniel Ricciardo fifth, ahead of McLaren's Lando Norris, and the second Racing Point of Lance Stroll. Ferrari's Charles Leclerc was only 10th.
Ferrari's predictions that they would be off the pace were accurate. They discovered an aerodynamic flaw with their car design after pre-season testing and are working on developments to fix the problem
Team boss Mattia Binotto said on Friday: "We pushed a lot on our project on trying to seek a lot of downforce but what we developed was too fragile in terms of aero robustness on track. We are trying to take a step back and redevelop."
He said they hoped the first step in the right direction would come at the Hungarian Grand Prix in two weeks' time.
On the race-simulation runs at the end of second practice, Mercedes' advantage looked as big as ever, Hamilton and Bottas a comfortable half-second plus clear of Red Bull and Ferrari, with the Racing Points looking as if they could challenge for podium positions, and McLaren and Renault also in the mix.