SINGAPORE: George Russell in a Mercedes topped the timesheets Friday in the only practice session for the Singapore Grand Prix at a Marina Bay Circuit enveloped in smoky haze caused by fires in Indonesia.

Charles Leclerc's Ferrari was second on a dusty surface with the McLaren of Lando Norris third as drivers and teams had just one hour-long session to maximise their set-ups before sprint qualifying later on Friday.

Singapore is featuring a sprint race for the first time and the only practice session took place before sunset, not ideal preparation for the Marina Bay Circuit's night race on Sunday.

Russell will start from the back of the grid for Sunday's race after taking a penalty for using too many engine components, but he can still compete for pole postion in Saturday's sprint race.