Hamilton had two sessions to forget as he could only come fourth in the first 90 minutes of running and seventh in the second, before having to pit early with a hydraulic problem.
Rosberg’s flying lap of the 5.065 kilometre (3.14 miles) Marina Bay circuit in 1min 44.152sec enabled him to bounce back after crashing in the first practice session earlier in the day.
Formula One supremo Bernie Ecclestone and Chase Carey of Liberty Media, the sports new chairman, arrived at the track in time for second practice and would have liked what they saw at the spectacular night event set against the skyscape of downtown Singapore.
Sunday’s race is shaping up already into a three-way tussle between Mercedes, Ferrari and Red Bull after Kimi Raikkonen was second fastest in the Ferrari, just 0.275 sec behind Rosberg.
Then came the Red Bull of Max Verstappen, using a new upgraded Renault engine, just ahead of his teammate Daniel Ricciardo.
Last year’s winner Sebastian Vettel was fifth quickest in his Ferrari.
Rosberg is just two points behind championship leader Hamilton after back-to-back wins in Belgium and Italy.
Victory in his 200th grand prix start on Sunday would put the German back on top of the standings he had led at one stage by 43 points earlier in the season.
