Lewis Hamilton has set the pace in the first practice session ahead of Sunday's Japanese Grand Prix at Suzuka.
The 28-year-old came in ahead of Mercedes teammate Nico Rosberg, with Red Bull duo Sebastian Vettel and Mark Webber coming third and fourth respectively.
Both Ferrari and Lotus Renault drivers also finished back to back, with Felipe Massa going faster than Fernando Alonso and Romain Grosjean besting Kimi Raikkonen.
Sergio Perez and Daniel Ricciardo completed the top 10, with second practice due to start at 6am (BST).
Full standings:
1. Lewis Hamilton (Mercedes)
2. Nico Rosberg (Mercedes)
3. Sebastian Vettel (Red Bull)
4. Mark Webber (Red Bull)
5. Felipe Massa (Ferrari)
6. Fernando Alonso (Ferrari)
7. Romain Grosjean (Lotus Renault)
8. Kimi Raikkonen (Lotus Renault)
9. Sergio Perez (McLaren)
10. Daniel Ricciardo (Toro Rosso)
11. Jenson Button (McLaren)
12. Nico Hulkenberg (Sauber)
13. Jean-Eric Vergne (Toro Rosso)
14. Adrian Sutil (Force India)
15. Pastor Maldonado (Williams)
16. Valeri Bottas (Williams)
17. Paul di Resta (Force India)
18. Esteban Gutierrez (Sauber)
19. Heiko Kovalainen (Caterham)
20. Jules Bianchi (Marussia)
21. Giemo van der Garde (Caterham)
22. Max Chilton (Marussia)
