Daniel Ricciardo topped the timesheets by a dominant margin ahead of teammate Max Verstappen, as Red Bull marked themselves out as contenders for victory on the opening day of Singapore Grand Prix practice.
Ricciardo put in a dazzling one minute 40.852 second lap under the floodlights, setting a new record around the Marina Bay street circuit after having already lowered the earlier benchmark with the fastest time in the opening session.
His effort was a massive 0.556 seconds quicker than Verstappen's best. Championship leader Lewis Hamilton meanwhile, chasing a hat-trick of wins this weekend, was third fastest after having been fourth in the opening session.
His title rival Sebastian Vettel, second in the evening, was inconspicuous at night with only the 11th fastest time.
Singapore's tight twists are expected to play to Ferrari and Red Bull's strengths and Vettel briefly lit up the timing screens. Valtteri Bottas, who agreed a one-year contract extension with Mercedes, ended the day fourth-fastest.