Sebastian Vettel and Ferrari have laid down the early marker to their rivals on the first morning of pre-season testing.
The German topped both the lap times and the lap count in Barcelona with an impressive 1m18.161s, two seconds faster than the best time on Day 1 last year.
In a year when the Scuderia is desperate to finally beat Mercedes, Vettel also completed more than a full race distance with 72 laps, three more than Valtteri Bottas in the Silver Arrow.
Sergio Perez was second and the only other driver to go sub-1m20s in the morning, as the new Racing Point car made its track debut.
Bottas followed in third on a typically regimental morning for Mercedes with Lewis Hamilton to take over in the afternoon.
Kimi Raikkonen caused a red flag within the first 10 minutes after spinning into the gravel at Turn 5 on his first lap in the Alfa Romeo, but the Finn recovered a produced a solid stint in the final hour, eventually finishing fourth.
Plenty of attention was on Red Bull and how their first day with Honda would develop and, despite a slow start, Max Verstappen would get into his stride with a solid 52 laps.
Interestingly, the RB15 also sat atop the speed trap at 320kph, but the team eased into testing with the fifth best time in the morning.
McLaren & Renault sat sixth and seventh as both focused on reliability over performance and it worked as the two French-powered teams managed 56 and 65 laps respectively.
The lowest lap count went to Haas and Romain Grosjean with just 18 as a fuel pressure issue saw the VF-19 cause the second red flag of the morning by coming to a halt at the final chicane.
Romain would complete six laps before lunch, however, so expect them to try and make up for lost time in the afternoon.
Bringing up the timesheet was Daniil Kvyat in the Toro Rosso, as the junior Red Bull team made a cautious start to pre-season.
The one team missing from the track is Williams, who confirmed they would not be ready to take part on Monday.