Nico Rosberg outpaced reigning world champion Lewis Hamilton to emerge as the fastest driver in the first practice session of the Singapore Grand Prix on Friday.
The German with his new power unit was 0.319 seconds quicker than his Mercedes team mate Hamilton, who maintains a 53-point lead over Rosberg in the drivers' championship standing after winning the Italian Grand Prix, Sport24 reported.
Red Bull's Daniel Ricciardo finished third ahead of four-time world champion Sebastian Vettel.
Hamilton is bidding to equal his Formula One idol Ayrton Senna's record of 41 race wins at this weekend's race.
A victory would see the Mercedes driver not only match Senna's feat in exactly the same number of races, but also strengthen his bid of equaling the late Brazilian's career haul of three world titles.