Kevin Korjus threw his hat into the ring as a contender for the Macau Grand Prix by going fastest in Friday's free practice session.
The Estonian put in a lap that would have put him second in Thursday's qualifying session with his Double R Racing Dallara-Mercedes.
Korjus was one of several drivers not to use new tyres in Thursday qualifying, and therefore was able to use two new Yokohamas in free practice to get an idea of grip for afternoon qualifying.
"We made a few adjustments from yesterday and put new tyres on the left," said the GP3 ace.
"I think that made a little bit of difference, but qualifying will be hard - the field is so closely matched this morning."
Tom Blomqvist stayed on the same set with which he completed all of Thursday's running to go second fastest, just 0.063 seconds behind Korjus, in the same Fortec Motorsport Dallara-Mercedes qualified on pole last year by Alex Lynn.
Carlin's drivers also stayed on old rubber, with Jazeman Jaafar and Harry Tincknell heading the squad's sextet of Dallara-Volkswagens in third and fourth respectively.
Thursday morning pacesetter Lynn was fifth in his Prema Powerteam Dallara-Mercedes, followed by two more Carlin runners, Carlos Sainz Jr and Antonio Felix da Costa.
Both overnight front-row men, Felix Rosenqvist (11th) and da Costa, appeared to use the session more to trial set-ups for later in the weekend.
Three more UK drivers - Alexander Sims, Will Buller and Jordan King - completed the top 10.
King was one of three drivers to crash at the tight Police bend during the session, although his was the lightest impact and he was able to rejoin after replacing the front wing.
Lucas Auer's impact was considerably heavier, swiping the left side of his Prema car against the barriers and causing a red flag.
Stefano Coletti later had an even bigger impact, although his car was craned away - with the Monegasque still aboard - under yellow flags.
Other drivers not to complete the session included European champion Raffaele Marciello, who went straight on at the Melco hairpin and felt it was too unsafe to reverse back out, Katsumasa Chiyo (who returned with a deranged left-front corner) and Dennis van de Laar.
Pos Driver Team/Car Time Gap 1. Kevin Korjus Double R Dallara-Merc 2m12.817s 2. Tom Blomqvist Fortec Dallara-Merc 2m12.880s +0.063s 3. Jazeman Jaafar Carlin Dallara-VW 2m13.021s +0.204s 4. Harry Tincknell Carlin Dallara-VW 2m13.024s +0.207s 5. Alex Lynn Prema Dallara-Merc 2m13.096s +0.279s 6. Carlos Sainz Jr Carlin Dallara-VW 2m13.111s +0.294s 7. Antonio Felix da Costa Carlin Dallara-VW 2m13.117s +0.300s 8. Alexander Sims T-Sport Dallara-Nissan 2m13.339s +0.522s 9. Will Buller Fortec Dallara-Merc 2m13.382s +0.565s 10. Jordan King Carlin Dallara-VW 2m13.453s +0.636s 11. Felix Rosenqvist Mucke Dallara-Merc 2m13.471s +0.654s 12. Pipo Derani Fortec Dallara-Merc 2m13.498s +0.681s 13. Raffaele Marciello Prema Dallara-Merc 2m13.577s +0.760s 14. Stefano Coletti Eurointernational Dallara-Merc 2m13.944s +1.127s 15. Yuhi Sekiguchi Mucke Dallara-Merc 2m14.084s +1.267s 16. Antonio Giovinazzi Double R Dallara-Merc 2m14.296s +1.479s 17. Esteban Ocon Prema Dallara-Merc 2m14.678s +1.861s 18. Nicholas Latifi Carlin Dallara-VW 2m14.926s +2.109s 19. Lucas Auer Prema Dallara-Merc 2m14.936s +2.119s 20. John Bryant-Meisner Fortec Dallara-Merc 2m15.215s +2.398s 21. Ed Jones Fortec Dallara-Merc 2m15.239s +2.422s 22. Lucas Wolf URD Dallara-Mercedes 2m15.418s +2.601s 23. Sean Gelael Double R Dallara-Merc 2m15.858s +3.041s 24. Katsumasa Chiyo B-Max Dallara-Toyota 2m15.860s +3.043s 25. Dennis van de Laar Mucke Dallara-Merc 2m16.020s +3.203s 26. Yuichi Nakayama TOM'S Dallara-Toyota 2m16.035s +3.218s 27. Nelson Mason Zeller Dallara-Merc 2m16.076s +3.259s 28. Sun Zheng Double R Dallara-Merc 2m19.390s +6.573s