Nico Rosberg has bettered his Mercedes teammate Lewis Hamilton in both practice sessions on Friday ahead of the Bahrain Grand Prix.
The 30-year-old topped the timesheet in the second practice under the lights, while Hamilton finished second and McLaren's Jenson Button was surprisingly third fastest.
Haas driver Romain Grosjean set the pace early in the session when he clocked a lap of 1:32.485, but it was soon surpassed as more drivers made their way onto the track.
Rosberg, who won the Australian Grand Prix a fortnight ago, surged to the top of the timesheets on soft tyres in his Mercedes after recording a lap time of 1:32.173 and he kept up the pace throughout the practice.
Sebastian Vettel had some trouble as he vacated his Ferrari after pulling off the track, but still managed to finish sixth fastest in the session.
Full P2 results:
1. Nico Rosberg (Mercedes)
2. Lewis Hamilton (Mercedes)
3. Jenson Button (McLaren)
4. Max Verstappen (Toro Rosso)
5. Kimi Raikkonen (Ferrari)
6. Sebastian Vettel (Ferrari)
7. Daniil Kyvat (Red Bull)
8. Valtteri Bottas (Williams)
9. Daniel Ricciardo (Red Bull)
10. Felipe Massa (Williams)
11. Stoffel Vandoorne (McLaren)
12. Esteban Gutierrez (Haas)
13. Carlos Sainz (Toro Rosso)
14. Romain Grosjean (Haas)
15. Sergio Perez (Force India)
16. Kevin Magnussen (Renault)
17. Nico Hulkenberg (Force India)
18. Jolyon Palmer (Renault)
19. Pascal Wehrlein (Manor)
20. Marcus Ericsson (Sauber)
21. Felipe Nasr (Sauber)
22. Rio Haryanto (Manor)