Lewis Hamilton boosted his hopes of keeping the world championship alive by topping both practice sessions on Friday ahead of Sunday's crucial Brazilian Grand Prix.

The defending champion topped the timesheet in the first practice earlier this afternoon, and maintained his place after the second session, finishing 0.03s faster than Mercedes teammate and title rival Nico Rosberg.

Rosberg will go into Sunday's race at Interlagos knowing that victory will secure the championship, but Hamilton - who trails the German by 19 points - can keep the race alive with a maiden victory in Brazil.

Williams pair Valtteri Bottas and Felipe Massa were the closest challengers to Mercedes, while Red Bull's Daniel Ricciardo and Max Verstappen made up the top six.

Saturday will see the final practice and qualifying before the potentially title-deciding race on Sunday.

1. Lewis Hamilton (Mercedes)
2. Nico Rosberg (Mercedes)
3. Valtteri Bottas (Williams)
4. Felipe Massa (Williams)
5. Daniel Ricciardo (Red Bull)
6. Max Verstappen (Red Bull)
7. Sebastian Vettel (Ferrari)
8. Kimi Raikkonen (Ferrari)
9. Nico Hulkenberg (Force India)
10. Jenson Button (McLaren)
11. Fernando Alonso (McLaren)
12. Daniil Kvyat (Toro Rosso)
13. Carlos Sainz Jr (Toro Rosso)
14. Sergio Perez (Force India)
15. Romain Grosjean (Haas F1)
16. Kevin Magnussen (Renault)
17. Felipe Nasr (Sauber)
18. Esteban Ocon (Manor)
19. Jolyon Palmer (Renault)
20. Esteban Gutierrez (Haas F1)
21. Marcus Ericsson (Sauber)
22. Pascal Wehrlein (Manor)