From the moment he hit the front, Mark Webber was unstoppable in Friday's opening practice at Sepang, finishing 1.665s ahead of Lewis Hamilton.
The Aussie, who needs to assert his claim at Red Bull Racing, clocked a 1:37.651 to easily take the P1 slot while Hamilton was a distant second.
Michael Schumacher found pace as he came home in third place, however, the German was over two seconds slower than Webber around the Sepang circuit.
Nico Hulkenberg shone in his role as Force India's test driver, taking fourth place ahead of his Williams replacement Pastor Maldonado.
Felipe Masas, Nick Heidfeld and Rubens Barrichello completed the top eight in a session that saw both Renault drivers suffer major brake problems and a suspension failure for Jerome D'Ambrosio.
Report: Track and air temperature were both up into the high 20s despite the early morning start at Sepang while clouds gathered overhead. A few test drivers were in action in Practice One with Nico Hulkenberg, Daniel Ricciardo and Davide Valsecchi out for Force India, Toro Rosso and Team Lotus respectively.
Hulkenberg was the first to post a time, a 1:44.557, which he soon lowered. Narain Karthikeyan ventured out for his first timed lap of the morning with plumes of smoke pouring out of the back of his Hispania. Game over as the Indian driver stopped out on track.
Nick Heidfeld was the next to lead the way with a 1:40.525, however, he then ran into problems as he locked up resulted in his brake sticking to his front right wheel. He made it back to the pits with his tyre and the floor of his car scrapping against the track.
He was in the P1 slot after the first half an hour, followed by Pastor Maldonado, Michael Schumacher, Nico Hulkenberg, Sergio Perez, Nico Rosberg, Kamui Kobayashi and Valsecchi. Tonio Liuzzi was the only other driver to have posted a lap time.
Mark Webber ventured out and quickly headed to the top of the timesheets, putting over a second between himself and the chasing pack. Lewis Hamilton joined the action, taking second place only for Webber to put in three purple sectors to again extend his advantage. Maldonado improved to third place but was over two seconds behind Webber.
With 30 minutes remaining, the only drivers not to have set times were Felipe Massa, despite completing 11 laps in and out of the pits, Vitaly Petrov, whose Renault team were working on his car, and Karthikeyan, who broke down early in the session. Petrov finally ventured out, put in a time that was 11 seconds off the pace, and then went off the track at Turn Nine, beaching his car in the gravel. The accident, though, was by no means his fault as his tyre disintegrated, putting him into the gravel. He reported "brakes" to his team, a major problem for Renault as both cars have now suffered serious brake problems.
Hamilton ran off the track at Turn Eight and moments later, Fernando Alonso did the same. Meanwhile, Webber was a man on a mission and extended his lead over Hamilton at the front to 1.665s. Jerome D'Ambrosio was the next casualty as he went off at the hairpin with what appears to be suspension failure. Once again, a crash that was by no means the driver's fault.
The session ended with Webber on top with a 1:37.651. Hamilton was second, 1.665s adrift, while Schumacher finished in third place ahead of Hulkenberg, Maldonado, Massa, Heidfeld and Barrichello.
Times
01. Mark Webber Red Bull 1:37.651 22 laps
02. Lewis Hamilton McLaren 1:39.316 16 laps
03. Michael Schumacher Mercedes GP 1:39.791 29 laps
04. Nico Hulkenberg Force India F1 1:40.377 23 laps
05. Pastor Maldonado Williams 1:40.443 31 laps
06. Felipe Massa Ferrari 1:40.453 22 laps
07. Nick Heidfeld Renault 1:40.525 6 laps
08. Rubens Barrichello Williams 1:40.581 21 laps
09. Fernando Alonso Ferrari 1:40.601 23 laps
10. Nico Rosberg Mercedes GP 1:40.646 29 laps
11. Adrian Sutil Force India F1 1:40.734 21 laps
12. Daniel Ricciardo Toro Rosso 1:40.748 23 laps
13. Jaime Alguersuari Toro Rosso 1:40.770 24 laps
14. Kamui Kobayashi Sauber 1:40.872 27 laps
15. Jenson Button McLaren 1:40.927 16 laps
16. Jarno Trulli Team Lotus 1:41.620 21 laps
17. Sebastian Vettel Red Bull 1:41.627 18 laps
18. Sergio Perez Sauber 1:41.642 24 laps
19. Timo Glock Virgin Racing 1:42.154 18 laps
20. Jerome d' Ambrosio Virgin Racing 1:42.540 20 laps
21. Davide Valsecchi Team Lotus 1:44.054 18 laps
22. Vitantonio Liuzzi Hispania 1:45.228 20 laps
23. Narain Karthikeyan Hispania 1:46.267 10 laps
24. Vitaly Petrov Renault 01:47.932 4 laps
