Sebastian Vettel set the fastest time during first practice for the Singapore Grand Prix.
The session started in damp conditions after heavy rain fell a few hours beforehand. Drivers briefly sampled the circuit with wet and Intermediate tyres, before the track dried sufficiently enough for the soft tyre to be used for the majority of the session.
As darkness fell at Marina Bay, the times swiftly improved. After an early period where Kamui Kobayashi was fastest, championship contenders Lewis Hamilton and Sebastian Vettel traded quickest lap times. The duo were comfortably clear of Jenson Button and Fernando Alonso.
Yellow flags came out briefly when Pastor Maldonado and Sergio Perez ran wide at Turn 9 on separate occasions.
Second practice gets under way at 21:30 local time.