Rosberg set the pace with a lap of 1:42.584 at the start of Q3 that was good enough to leave the field trailing in his wake and over 0.7s clear of team-mate Hamilton early on.
Daniel Ricciardo of Red Bull improved from fourth to second late in the session, but Hamilton could not enhance his prospects as his toils in practice continued into qualifying.
Rosberg was unable to improve on his time on his final attempt but didn't need to, with Hamilton's scruffy lap seeing the championship leader also fail to improve. That opened the door for the Australian to take second, with Max Verstappen finishing the session 0.040s slower than Hamilton in fourth place.
Singapore Grand Prix
Podcast: Singapore GP review
- 1. Nico Rosberg GER Mercedes-Mercedes 1m 42.584s
- 2. Daniel Ricciardo AUS Red Bull-TAG Heuer 1m 43.115s
- 3. Lewis Hamilton GBR Mercedes-Mercedes 1m 43.288s
- 4. Max Verstappen NED Red Bull-TAG Heuer 1m 43.328s
- 5. Kimi Raikkonen FIN Ferrari-Ferrari 1m 43.540s
- 6. Carlos Sainz Jr ESP Toro Rosso-Ferrari 1m 44.197s
- 7. Daniil Kvyat RUS Toro Rosso-Ferrari 1m 44.469s
- 8. Nico Hulkenberg GER Force India-Mercedes 1m 44.479s
- 9. Fernando Alonso ESP McLaren-Honda 1m 44.553s
- 10. Sergio Perez MEX Force India-Mercedes 1m 44.582s
- 11. Valtteri Bottas FIN Williams-Mercedes 1m 44.740s
- 12. Felipe Massa BRZ Williams-Mercedes 1m 44.991s
- 13. Jenson Button GBR McLaren-Honda 1m 45.144s
- 14. Esteban Gutierrez MEX Haas-Ferrari 1m 45.593s
- 15. Romain Grosjean FRA Haas-Ferrari 1m 45.723s
- 16. Marcus Ericsson SWE Sauber-Ferrari 1m 47.827s
- 17. Kevin Magnussen DEN Renault-Renault 1m 46.825s
- 18. Felipe Nasr BRZ Sauber-Ferrari 1m 46.860s
- 19. Jolyon Palmer GBR Renault-Renault 1m 46.960s
- 20. Pascal Wehrlein GER MRT-Mercedes 1m 47.667s
- 21. Esteban Ocon FRA MRT-Mercedes 1m 48.296s
- 22. Sebastian Vettel GER Ferrari-Ferrari 1m 49.116s
While the Red Bull pair will be disappointed by the gap to Rosberg having been so competitive throughout the rest of the weekend, both Ricciardo and Verstappen will start the race on supersoft tyres - compared to ultrasofts for the rest of the top ten - after progressing through to Q2 on the supersofts.
Raikkonen was demoted to fifth, with Carlos Sainz also impressing with sixth place for Toro Rosso, one position ahead of team-mate Daniil Kvyat. Nico Hulkenberg, Fernando Alonso and Sergio Perez round out the top ten.
The end of Q2 saw two incidents as first Romain Grosjean hit the barrier at Turn 10. The Frenchman had been complaining of problems with his brakes all weekend and lost the rear of his car under braking, spinning backwards into the barrier.
With only a matter of seconds left on the clock, the track remained under double waved yellow flags to allow the session to end, but a few corners ahead Jenson Button also hit the barrier.
The 2009 world champion clipped the wall with his left rear exiting Turn 14, damaging the tyre and forcing him to stop two corners later. Despite the stricken cars, Perez managed to complete his lap and progress to Q3 at the expense of the two Williams cars. Valtteri Bottas will start 11th ahead of team-mate Felipe Massa, with Button, Esteban Gutierrez, Grosjean and Marcus Ericsson also eliminated.
Vettel was a casualty of Q1 due to a problem with his car, with the German believing his rear anti-roll bar was broken as he attempted his one run of the session. The Ferrari could be seen lifting a front wheel at every corner as Vettel still tried to post a time, but as he was already 0.2s slower than the time needed to advance he returned to the pits where Ferrari ran out of time to try and fix the problem.
Vettel will start from 22nd on the grid as a result, having posted the slowest time of the first part of qualifying. That left a space available for one of the Saubers or Renaults to progress, and it was Ericsson who delivered an impressive lap to go through by 0.4s. As a result the two Renault drivers dropped out, with Kevin Magnussen 17th ahead of Felipe Nasr and Jolyon Palmer.
Pascal Wehrlein will start from 20th ahead of Esteban Ocon and Vettel, having out-qualified his Manor team-mate by 0.6s.
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