Nico Rosberg put in the first laps in the new Mercedes W04 just hours ahead of the car's official launch.
The German driver, who is entering his fourth season with Mercedes, was in action at the Jerez circuit for promotional work.
Starting early this morning, Rosberg climbed into his W04 and begun putting in laps.
However, as testing only begins at the track on Tuesday, the laps were more like tours of the track than flat-out efforts.
As for the car, the most notable change to the W04 from last year's car is that it features the vanity panel adopted by McLaren, Ferrari and Sauber.
Lewis Hamilton was on hand to keep an eye - and a camera - on his team-mate's laps.
The W04 Makes Its Track Debut