Nico Rosberg topped the opening practice session of the 2015 season in Australia

The 2014 runner-up set the pace with a lap of 1:29.557 on the medium tyre, in a session dominated by the two Mercedes team-mates.

Lewis Hamilton was second in the sister W06 Hybrid, just +0.029 shy of Rosberg, to ensure the reigning champions ended the first session of 2015 with a 1-2.

Williams’ Valtteri Bottas was their closest rival, though he remained over a second off the pace with his 1:30.748 – the only driver bar Mercedes to dip below the 1:31 mark.

The Toro Rosso rookies Max Verstappen and Carlos Sainz were the two most active drivers during the session, completing 63 laps between them as they got their first taste of the Albert Park track. The pair were separated by just 0.053s – as well as the Ferrari of Sebastian Vettel – and in doing so made a solid start to their F1 careers with the fourth and sixth fastest times.

Meanwhile, the senior Red Bull team appeared to struggle, with Daniel Ricciardo complaining about the driveability of the Renault power unit and suffering a spin at the penultimate corner with 30 minutes remaining. While Renault has worked on boosting power ahead of the season, the delivery of the power was still offering the drivers some surprises on Friday. Ricciardo’s fastest time was quick enough for 10th behind the Lotus of Pastor Maldonado, the Ferrari of Kimi Raikkonen and the Williams of Felipe Massa.

McLaren continued its stop-start search for reliability, but despite hitting the track early in the session only managed 13 laps between both drivers. Of the cars that set a time they were only quicker than Romain Grosjean, whose Lotus had an issue until the final moments of the session when he completed five laps.

Pos Driver Car Time Gap Laps
1 Nico Rosberg Mercedes 1m29.557s 19
2 Lewis Hamilton Mercedes 1m29.586s 0.029s 19
3 Valtteri Bottas Williams/Mercedes 1m30.748s 1.191s 20
4 Carlos Sainz Jr. Toro Rosso/Renault 1m31.014s 1.457s 32
5 Sebastian Vettel Ferrari 1m31.029s 1.472s 13
6 Max Verstappen Toro Rosso/Renault 1m31.067s 1.510s 31
7 Felipe Massa Williams/Mercedes 1m31.188s 1.631s 19
8 Kimi Raikkonen Ferrari 1m31.310s 1.753s 14
9 Pastor Maldonado Lotus/Mercedes 1m31.451s 1.894s 22
10 Daniel Ricciardo Red Bull/Renault 1m31.570s 2.013s 9
11 Daniil Kvyat Red Bull/Renault 1m32.073s 2.516s 18
12 Sergio Perez Force India/Mercedes 1m32.247s 2.690s 22
13 Nico Hulkenberg Force India/Mercedes 1m32.261s 2.704s 19
14 Jenson Button McLaren/Honda 1m34.542s 4.985s 6
15 Kevin Magnussen McLaren/Honda 1m34.785s 5.228s 7
16 Romain Grosjean Lotus/Mercedes 2m17.782s 48.225s 5