Ferrari's Fernando Alonso has finished with the fastest time in the first practice session ahead of the Chinese Grand Prix.
The Spaniard was just under a second quicker than his closest rival, Nico Rosberg, as he clocked a time of 1:39.73.
Alonso's teammate Kimi Raikkonen was unable to enjoy similar success as the team battled problems in his car throughout the session, which ended without the former world champions recording a time.
There was also some frustration for Mercedes, who despite seeing Rosberg finish second quickest were forced to bring in Lewis Hamilton before the end of the session due to troubles with his suspension.
Red Bull's Daniel Ricciardo completed the top three in the opening practice, but his teammate Sebastian Vettel could only record the ninth-fastest time.
1. Fernando Alonso (Ferrari)
2. Nico Rosberg (Mercedes)
3. Daniel Ricciardo (Red Bull)
4. Jenson Button (McLaren)
5. Nico Hulkenberg (Force India)
6. Kevin Magnussen (McLaren)
7. Jean-Eric Vergne (Torro Rosso)
8. Lewis Hamilton (Mercedes)
9. Sebastian Vettel (Red Bull)
10. Felipe Massa (Williams)
11. Daniil Kvyat (Torro Rosso)
12. Romain Grosjean (Lotus)
13. Felipe Nasr (Williams)
14. Giedo van der Garde (Sauber)
15. Sergio Perez (Force India)
16. Pastor Maldonado (Lotus)
17. Kamui Kobayashi (Caterham)
18. Esteban Gutierrez (Sauber)
19. Jules Bianchi (Marussia)
20. Max Chilton (Marussia)
21. Marcus Ericsson (Caterham)
22. Kimi Raikkonen (Ferrari)