Britain's Alex Lynn topped the opening free practice session for the Macau Grand Prix.
A late run of two quick laps propelled the 2012 pole winner to the head of the times in his Prema Powerteam Dallara-Mercedes, allowing him to edge out last year's race victor Antonio Felix da Costa by six hundredths of a second.
The session began with light rain making the track slippery at the final two corners, Fisherman's Bend and R Bend.
This caught out Carlos Sainz Jr, who lost the rear end of his Carlin Dallara-Volkswagen at Fisherman's just 12 minutes into the 45-minute session and ricocheted into the barriers rear-end first.
Eleven minutes later, team-mate Jordan King understeered into the Armco at the same corner.
"The car felt nice, but I was cautious in those last two corners because I saw Carlos and Jordan stick it in," Lynn said. "It all felt really good.
"It's nice to carry on my form from last year [when Lynn was with Fortec Motorsport], and I think that the fact that we're competitive is a weight off Prema's mind [after the team struggled in Macau last year]."
Da Costa's Carlin machine just pipped fellow F3 returnee Stefano Coletti to second place.
The Monegasque lightly hit the wall at the Melco hairpin in the closing minutes but brought his EuroInternational Dallara-Merc back to the pits.
Felix Rosenqvist was also close at hand in fourth place.
The Swede had been set to go top in his Mucke Motorsport Dallara-Merc after a lap that featured the best split time in the tricky middle sector, but then he crashed at San Francisco Bend.
"I ran wide at Lisboa [the preceding corner] and got shit on my tyres," explained the European F3 Championship runner-up.
Alexander Sims was fifth fastest in T-Sport's ThreeBond/Nissan-powered Dallara, just ahead of Carlin-run Jazeman Jaafar.
Tom Blomqvist was the best of the Fortec contingent in seventh, ahead of steady-starting European F3 champ Raffaele Marciello and Prema team-mate Lucas Auer, with Double R Racing's Kevin Korjus rounding out the top 10.
The others not to complete the session due to incidents were former Macau GP podium finisher Yuhi Sekiguchi, Lucas Wolf and Sun Zheng.
Pos Driver Team/Car Time Gap 1. Alex Lynn Prema Dallara-Merc 2m14.495s 2. Antonio Felix da Costa Carlin Dallara-VW 2m14.556s +0.061s 3. Stefano Coletti Eurointernational Dallara-Merc 2m14.603s +0.108s 4. Felix Rosenqvist Mucke Dallara-Merc 2m14.662s +0.167s 5. Alexander Sims T-Sport Dallara-Nissan 2m14.849s +0.354s 6. Jazeman Jaafar Carlin Dallara-VW 2m14.864s +0.369s 7. Tom Blomqvist Fortec Dallara-Merc 2m15.169s +0.674s 8. Raffaele Marciello Prema Dallara-Merc 2m15.181s +0.686s 9. Lucas Auer Prema Dallara-Merc 2m15.247s +0.752s 10. Kevin Korjus Double R Dallara-Merc 2m15.384s +0.889s 11. Will Buller Fortec Dallara-Merc 2m15.449s +0.954s 12. Pipo Derani Fortec Dallara-Merc 2m15.796s +1.301s 13. Harry Tincknell Carlin Dallara-VW 2m16.410s +1.915s 14. Antonio Giovinazzi Double R Dallara-Merc 2m16.540s +2.045s 15. Lucas Wolf URD Dallara-Mercedes 2m16.591s +2.096s 16. Dennis van de Laar Mucke Dallara-Merc 2m16.627s +2.132s 17. Yuichi Nakayama TOM'S Dallara-Toyota 2m16.943s +2.448s 18. Esteban Ocon Prema Dallara-Merc 2m17.474s +2.979s 19. Nicholas Latifi Carlin Dallara-VW 2m17.867s +3.372s 20. John Bryant-Meisner Fortec Dallara-Merc 2m18.081s +3.586s 21. Carlos Sainz Jr Carlin Dallara-VW 2m18.453s +3.958s 22. Ed Jones Fortec Dallara-Merc 2m18.872s +4.377s 23. Katsumasa Chiyo B-Max Dallara-Toyota 2m19.488s +4.993s 24. Nelson Mason Zeller Dallara-Merc 2m19.719s +5.224s 25. Yuhi Sekiguchi Mucke Dallara-Merc 2m20.095s +5.600s 26. Sean Gelael Double R Dallara-Merc 2m20.311s +5.816s 27. Jordan King Carlin Dallara-VW 2m21.234s +6.739s 28. Sun Zheng Double R Dallara-Merc 2m26.053s +11.558s