Nico Rosberg blitzed the competition, including Lewis Hamilton, as cooler conditions in Bahrain meant a dramatic fall in lap times in FP1.
Friday’s first practice at the Sakhir circuit got underway in cooler than expected conditions following Thursday’s rain.
Mercedes claimed the 1-2, a position they held for 70 of the 90 minutes.
Rosberg set the early pace with a 1:33.592 while Hamilton was 0.081s slower. The Mercedes pairing were, however, immediately out on the quicker soft tyres whereas many of their rivals ventured out for an early run on the medium tyres.
But despite swapping to the softs later in the session, they were not able to depose the championship leaders, who upped the pace on their second run.
Again out on the soft tyres Rosberg stormed to a 1:32.294 while Hamilton improved his time but could not stop the German from extending his advantage to 0.505s.
Kimi Raikkonen was the closest challenger but finished a massive 1.8s down despite having set his best time on the soft tyres.
He finished ahead of Daniel Ricciardo and Daniil Kvyat while Nico Hulkenberg, Carlos Sainz and Max Verstappen completed the top eight.
Romain Grosjean was ninth for Haas ahead of Felipe Massa while Sebastian Vettel finished down in 11th place.
He had a slightly unusual problem early in the session as the German reported that was getting wet. It wasn’t rain, it was his drinks bottle leaking. That kept him the pits for a while and he covered 14 laps.
As for debutant Stoffel Vandoorne, the McLaren test driver was P18 as he subbed for the injured Fernando Alonso. The Beglian racer’s best time was a 1:36.392.
1 Nico Rosberg Mercedes 1:32.294 24 laps
2 Lewis Hamilton Mercedes 1:32.799 0.505 24 laps
3 Kimi Raikkonen Ferrari 1:34.128 1.834 16 laps
4 Daniel Ricciardo Red Bull Racing 1:34.461 2.167 27 laps
5 Daniil Kvyat Red Bull Racing 1:34.541 2.247 30 laps
6 Nico Hulkenberg Force India 1:34.601 2.307 28 laps
7 Carlos Sainz Jr Toro Rosso 1:34.793 2.499 21 laps
8 Max Verstappen Toro Rosso 1:34.860 2.566 19 laps
9 Romain Grosjean Haas F1 1:35.000 2.706 18 laps
10 Felipe Massa Williams 1:35.006 2.712 19 laps
11 Sebastian Vettel Ferrari 1:35.073 2.779 14 laps
12 Valtteri Bottas Williams 1:35.174 2.880 21 laps
13 Esteban Gutierrez Haas F1 1:35.309 3.015 19 laps
14 Jenson Button McLaren 1:35.440 3.146 28 laps
15 Kevin Magnussen Renault 1:35.490 3.196 27 laps
16 Marcus Ericsson Sauber 1:35.728 3.434 30 laps
17 Pascal Wehrlein Manor Racing 1:36.371 4.077 26 laps
18 Stoffel Vandoorne McLaren 1:36.392 4.098 25 laps
19 Felipe Nasr Sauber 1:36.719 4.425 24 laps
20 Jolyon Palmer Renault 1:36.939 4.645 28 laps
21 Alfonso Celis Force India 1:37.287 4.993 23 laps
22 Rio Haryanto Manor Racing 1:37.714 5.420 27 laps
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