Esteban Gutierrez topped the half hour of free practice ahead of qualifying on Friday for GP2's first ever race around the streets of Singapore.
A heavy thunderstorm in the hour before the session began soaked the track, making conditions perilous with puddles proving slow to evaporate in the humid conditions.
Gutierrez lapped his Lotus GP machine in 2m14.339s, 0.332s quicker than Racing Engineering's Fabio Leimer. Stefano Coletti was third fastest for Rapax, despite overshooting the same corner twice, ahead of Gutierrez's team-mate James Calado and Addax's Johnny Cecotto Jr.
With both championships to be decided this weekend in the season finale, it was Lotus that threw down the gauntlet in the teams' title race - the Paris-based team two points behind fellow French outfit DAMS and very much at the top of the times throughout the session.
Both Calado and Gutierrez are already ruled out of the drivers' title race, however, which will be decided between Davide Valsecchi of DAMS and Luiz Razia of Arden. They remained locked together during the session, but in the lower reaches of the timesheets. Valsecchi ended up 14th and Razia down in 20th.
Valsecchi leads Razia by 25 points, and with four points up for grabs in qualifying tonight, Razia will have to find something special to eat into his rival's advantage.
There were numerous spins, straight-lining of chicanes and overshoots down the escape road, but no actual damage was done during the session. Stephane Richelmi came closest, spinning his Trident car onto the Anderson Bridge but just staying out of the wall.
Pos Driver Team Time Gap
1. Esteban Gutierrez Lotus 2m14.339s
2. Fabio Leimer Racing Engineering 2m14.671s + 0.332s
3. Stefano Coletti Rapax 2m15.284s + 0.945s
4. James Calado Lotus 2m15.335s + 0.996s
5. Johnny Cecotto Jr Addax 2m15.364s + 1.025s
6. Giedo van der Garde Caterham 2m15.436s + 1.097s
7. Simon Trummer Arden 2m15.729s + 1.390s
8. Rio Haryanto Carlin 2m15.734s + 1.395s
9. Felipe Nasr DAMS 2m16.232s + 1.893s
10. Julian Leal Trident 2m16.233s + 1.894s
11. Fabio Onidi Coloni 2m16.306s + 1.967s
12. Rodolfo Gonzalez Caterham 2m16.325s + 1.986s
13. Nathanael Berthon Racing Engineering 2m16.461s + 2.122s
14. Davide Valsecchi DAMS 2m16.510s + 2.171s
15. Nigel Melker Ocean 2m16.535s + 2.196s
16. Jolyon Palmer iSport 2m16.623s + 2.284s
17. Sergio Canamasas Lazarus 2m16.956s + 2.617s
18. Luca Filippi Coloni 2m17.243s + 2.904s
19. Victor Guerin Ocean 2m17.329s + 2.990s
20. Luiz Razia Arden 2m17.524s + 3.185s
21. Stephane Richelmi Trident 2m17.962s + 3.623s
22. Max Chilton Carlin 2m18.033s + 3.694s
23. Marcus Ericsson iSport 2m18.635s + 4.296s
24. Jake Rosenzweig Addax 2m18.906s + 4.567s
25. Rene Binder Lazarus 2m19.745s + 5.406s
26. Ricardo Teixeira Rapax 2m24.101s + 9.762s