Championship contender Lewis Hamilton has topped the timesheet for Mercedes in the second practice session of the Singapore Grand Prix at the Marina Bay Street Circuit.
Ferrari's Fernando Alonso, who clocked the fastest time in the first practice, finished one tenth off the pace, while Red Bull's Daniel Ricciardo finished third quickest.
Ferrari's Kimi Raikkonen clocked the fourth-fastest time under the floodlights, while Hamilton's teammate and title rival Nico Rosberg could only record the 13th-quickest time.
Almost an hour into practice, the session was red-flagged when Pastor Maldonado smashed his Lotus into the barriers after oversteering on the exit of Turn 10.
The Venezuelan driver walked away from the incident unharmed, but the front right corner of his car was destroyed and a crane was required to remove the Lotus from the track.
Ahead of Sunday's race, Rosberg leads Hamilton by 22 points in the drivers' standings.
Full standings
1. Lewis Hamilton (Mercedes)
2. Fernando Alonso (Ferrari)
3. Daniel Ricciardo (Red Bull)
4. Kimi Raikkonen (Ferrari)
5. Sebastian Vettel (Red Bull)
6. Kevin Magnussen (McLaren)
7. Jenson Button (McLaren)
8. Sergio Perez (Force India)
9. Nico Hulkenberg (Force India)
10. Daniil Kvyat (Toro Rosso)
11. Jean-Eric Vergne (Toro Rosso)
12. Romain Grosjean (Lotus)
13. Nico Rosberg (Mercedes)
14. Pastor Maldonado (Lotus)
15. Adrian Sutil (Sauber)
16. Esteban Gutierrez (Sauber)
17. Felipe Massa (Williams)
18. Valterri Bottas (Williams)
19. Jules Bianchi (Marussia)
20. Max Chilton (Marussia)
21. Kamui Kobayashi (Caterham)
22. Marcus Ericsson (Caterham)