Red Bull's Mark Webber led the first free practice session at the Malaysian Grand Prix on Friday with championship leader Kimi Raikkonen snapping at his heels.

Webber clocked the fastest time of 1min 36.935sec around a sun-baked Sepang circuit with Raikkonen, winner of last week's season-opening Australian Grand Prix, just seven-hundredths of a second slower.

Sebastian Vettel, Red Bull's three-time defending world champion, was third quickest in the 90-minute warm-up drive, with his rival Fernando Alonso of Ferrari fourth.

Nico Rosberg, Adrian Sutil, Felipe Massa, Paul di Resta, Lewis Hamilton and Romain Grosjean rounded out the top 10 in the largely experimental session as teams size up their best options for Sunday's race.

Tropical heat and sudden downpours make the Malaysian Grand Prix one of the most demanding of the season with an extra challenge this year in preserving Pirelli's new, faster-degrading tyres.

The drivers will head out for another practice session at 2:00 pm (0600 GMT) with a third run-out on Saturday, followed by qualifying. The race is on Sunday.


Here is a rundown of the first and second free practice times on Friday for the Malaysian Grand Prix:

Free practice 2

1. Kimi Raikkonen (FIN) Lotus 1:36.569, 2. Sebastian Vettel (GER) Red Bull Racing 1:36.588, 3. Felipe Massa (BRA) Scuderia Ferrari 1:36.661, 4. Fernando Alonso (ESP) Scuderia Ferrari 1:36.985, 5. Mark Webber (AUS) Red Bull Racing 1:37.026, 6. Romain Grosjean (FRA) Lotus 1:37.206, 7. Nico Rosberg (GER) Mercedes 1:37.448, 8. Paul di Resta (GBR) Force India 1:37.571, 9. Lewis Hamilton (GBR) Mercedes 1:37.574, 10. Adrian Sutil (GER) Force India 1:37.788, 11. Sergio Perez (MEX) McLaren Mercedes 1:37.838, 12. Jenson Button (GBR) McLaren Mercedes 1:37.865, 13. Nico Hulkenberg (GER) Sauber 1:38.068, 14. Esteban Gutierrez (MEX) Sauber 1:38.645, 15. Jean-Eric Vergne (FRA) Scuderia Toro Rosso 1:38.738, 16. Pastor Maldonado (VEN) Williams 1:38.801, 17. Daniel Ricciardo (AUS) Scuderia Toro Rosso 1:38.904, 18. Jules Bianchi (FRA) Marussia 1:39.508, 19. Valtteri Bottas (FIN) Williams 1:39.660, 20. Charles Pic (FRA) Caterham 1:40.757, 21. Giedo van der Garde (NED) Caterham 1:40.768, 22. Max Chilton (GBR) Marussia 1:41.438

Free practice 1

1. Mark Webber (AUS) Red Bull Racing 1:36.935, 2. Kimi Raikkonen (FIN) Lotus 1:37.003, 3. Sebastian Vettel (GER) Red Bull Racing 1:37.104, 4. Fernando Alonso (ESP) Scuderia Ferrari 1:37.319, 5. Nico Rosberg (GER) Mercedes 1:37.588, 6. Adrian Sutil (GER) Force India 1:37.769, 7. Felipe Massa (BRA) Scuderia Ferrari 1:37.771, 8. Paul di Resta (GBR) Force India 1:37.773, 9. Lewis Hamilton (GBR) Mercedes 1:37.840, 10. Romain Grosjean (FRA) Lotus 1:37.915, 11. Jenson Button (GBR) McLaren Mercedes 1:38.173, 12. Pastor Maldonado (VEN) Williams 1:38.673, 13. Sergio Perez (MEX) McLaren Mercedes 1:38.830, 14. Nico Hulkenberg (GER) Sauber 1:39.054, 15. Esteban Gutierrez (MEX) Sauber 1:39.204, 16. Valtteri Bottas (FIN) Williams 1:39.208, 17. Jean-Eric Vergne (FRA) Scuderia Toro Rosso 1:39.284, 18. Daniel Ricciardo (AUS) Scuderia Toro Rosso 1:39.567, 19. Giedo van der Garde (NED) Caterham 1:40.728, 20. Jules Bianchi (FRA) Marussia 1:40.996, 21. Charles Pic (FRA) Caterham 1:41.163, 22. Max Chilton (GBR) Marussia 1:41.513