Nico Rosberg set the fastest time of first practice for the Malaysian Grand Prix as Lewis Hamilton stopped on track after four laps.
Reliability was a relative weakness for Mercedes in 2014, and problems surfaced again on Friday morning as Hamilton pulled to the side of the track at Turn 9 despite claiming he could have made it back to the pits. With Hamilton's car not delivering any telemetry, Mercedes said it was being cautious by asking him to stop and it was right to be as the team later confirmed an engine change was required.
Rosberg suffered from no such problems as he comfortably set the pace in the other Mercedes, clocking a 1:40.124. As in Melbourne, Ferrari was again the nearest challenger with Kimi Raikkonen just under 0.4s adrift in second place and Sebastian Vettel a further half second back as both cars improved right at the end of the session.
There were encouraging signs for two teams near the bottom of the times as Manor finally ran its car for the first time. Both Will Stevens and Roberto Merhi completed eight laps each, with Stevens the faster of the two but 6.5s off of Rosberg's pace on what was essentially an installation run for the car.
McLaren also showed signs of improvement, with both Fernando Alonso and Jenson Button completing solid running. Alonso ended the session 14th fastest - with the two Force Indias separating him from his team-mate - and was 2.7s off the pace, while the two cars managed 39 laps between them.
To highlight the gap between Mercedes, Ferrari and the rest, Romain Grosjean was 1.4s adrift of Rosberg in fourth place and 1.3s clear of Alonso's McLaren. Carlos Sainz Jr finished the session in fifth place ahead of Daniel Ricciardo and Max Verstappen as all four Renault-powered cars finished the session in the top ten. Daniil Kvyat, however, complained of something "strange" to do with braking and power delivery.
Kvyat ended the session in ninth place behind Valtteri Bottas' Williams and ahead of Marcus Ericsson in the Sauber. Ferrari young driver Raffaele Marciello made his FP1 debut in the second Sauber, enjoying a solid session as he completed 13 laps and was half a second adrift of his team-mate.
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| Pos | Driver | Team | Time | Laps |
|---|---|---|---|---|
| 01 | N. Rosberg | Mercedes | 1:40.124 | 20 |
| 02 | K. Raikkonen | Ferrari | 1:40.497 | 17 |
| 03 | S. Vettel | Ferrari | 1:40.985 | 13 |
| 04 | R. Grosjean | Lotus | 1:41.543 | 14 |
| 05 | C. Sainz | Toro Rosso | 1:41.596 | 26 |
| 06 | D. Ricciardo | Red Bull | 1:41.787 | 15 |
| 07 | M. Verstappen | Toro Rosso | 1:41.803 | 23 |
| 08 | V. Bottas | Williams | 1:41.882 | 23 |
| 09 | D. Kvyat | Red Bull | 1:42.055 | 18 |
| 10 | M. Ericsson | Sauber | 1:42.064 | 16 |
| 11 | F. Massa | Williams | 1:42.103 | 23 |
| 12 | P. Maldonado | Lotus | 1:42.567 | 19 |
| 13 | R. Marciello | Sauber | 1:42.621 | 13 |
| 14 | F. Alonso | McLaren | 1:42.885 | 20 |
| 15 | N. Hulkenberg | Force India | 1:42.893 | 13 |
| 16 | S. Perez | Force India | 1:43.054 | 15 |
| 17 | J. Button | McLaren | 1:43.100 | 19 |
| 18 | W. Stevens | Manor | 1:46.686 | 8 |
| 19 | R. Merhi | Manor | 1:47.683 | 8 |
| 20 | L. Hamilton | Mercedes | 4 |
