Mercedes driver Lewis Hamilton led the way in a fast first free practice for the Singapore Grand Prix Friday which indicated the five-year-old lap record will fall this weekend.
Hamilton timed 1min 47.055sec in the largely experimental dusk session at the Marina Bay street circuit, less than two seconds off Kimi Raikkonen's 2008 record of 1:45.599.
Mark Webber, counting down the races until he leaves the sport this year, was second quickest with 1:47.420, ahead of his Red Bull team-mate and championship leader Sebastian Vettel (1:47.885).
Mercedes' Nico Rosberg, and Raikkonen and Romain Grosjean of Lotus occupied the next three places, ahead of Ferrari's Fernando Alonso, who is currently second in the overall standings.
Under a spectacular sunset in downtown Singapore, Grosjean lost an hour of testing with a steering problem, Webber skimmed a wall and Raikkonen sketchily ran wide on one corner.
A remodelled Turn 10, dubbed the "Singapore Sling" and once one of Formula One's most notorious corners, has helped slash lap times along with track resurfacing and smoother kerbs.
With Vettel closing on his fourth straight world title, debate over drivers' movements has dominated the race build-up after Ferrari re-hired their 2007 champion Raikkonen to pair with Alonso.
Ferrari's Felipe Massa and Nico Hulkenberg are both linked with Raikkonen's seat at Lotus, and the rumour mill has gone into overdrive with speculation that Alonso may consider jumping ship to McLaren.
2013 Formula 1 Singapore Grand Prix | Date: 20-22 September 2013 | Venue: Marina Bay Street Circuit | Tickets: $48 to $1,288 from www.singaporegp.sg