Ferrari led the way on the opening day of practice for this weekend's Malaysian Grand Prix with Sebastian Vettel topping the timesheets with a new track record. Teammate Kimi Raikkonen was second quickest, six tenths of a second behind Vettel's record pace.
Red Bull claimed P3 and 4 with Daniel Ricciardo the quicker of the two with Fernando Alonso a pleasing fifth for McLaren Honda.
Uncharacteristically for Mercedes, they were only sixth and seventh fastest.
The first session was held in wet conditions and delayed by thirty minutes due to the heavy rain while the second session was cut short by ten minutes after Romain Grosjean ran over a drain cover that punctured his right rear Pirelli and threw him into the barriers.
Thankfully the HaasF1 driver was uninjured in the shunt
Top ten:
| 1. Sebastian Vettel | Ferrari | 1:31.261 |
| 2. Kimi Raikkonen | Ferrari | +0.604 |
| 3. Daniel Ricciardo | Red Bull | +0.838 |
| 4. Max Verstappen | Red Bull | +0.848 |
| 5. Fernando Alonso | McLaren | +1.303 |
| 6. Lewis Hamilton | Mercedes | +1.416 |
| 7. Valtteri Bottas | Mercedes | +1.459 |
| 8. Sergio Perez | Force India | +1.601 |
| 9. Nico Hulkenberg | Renault | +1.799 |
| 10. Esteban Ocon | Force India | +1.835 |
