Hillspeed's Freddie Slater ended the first day of pre-event testing for the GB3 Championship with the fastest time of the day at Silverstone.
The British driver set his best time in the final session, and recorded a best lap of 1m52.498s, quicker than last year's pole position time. Slater was also fastest in the second session.
He ended the day 0.117s clear of Rodin Motorsport's Alex Ninovic, with the Australian's countryman and teammate Gianmarco Pradel third quickest, with each of the top-three setting their best times in the final test.
Kai Daryanani's session two time was enough to put the JHR Developments driver fourth overall on Thursday, 0.177s clear of Argenti with Prema's Lucas Fluxa.
Reigning F1 Academy champion Abbi Pulling was within half a second of Slater's outright pace, enough to put the third Rodin car sixth overall.
Having topped the opening session of the day, Xcel Motorsport's Patrick Heuzenroeder ended Thursday seventh in the combined times, 0.005s clear of Hillspeed's Kanato Le.
Hitech TGR's reigning British F4 champion Deagen Fairclough was ninth quickest courtesy of his session two effort, with Elite Motorsport's Will Macintyre completing the day's top-10.
A total of 27 drivers took part in today's test, with Fortec handing a first GB3 run for Emerson Fittipaldi Jr (son of F1 world champion Emerson), while Chris Dittmann Racing ran two cars including a maiden GB3 outing for F4 driver Divy Nandan.
Testing resumes on the Grand Prix circuit tomorrow, with two more sessions.
GB3 Championship, partnered by the BRDC, Silverstone combined Thursday test result:
1. Freddie Slater, Hillspeed, 1m52.498s
2. Alex Ninovic, Rodin Motorsport, +0.117s
3. Gianmarco Pradel, Rodin Motorsport, +0.173s
4. Kai Daryanani, JHR Developments, +0.195s
5. Lucas Fluxa, Argenti with Prema, +0.372s
6. Abbi Pulling, Rodin Motorsport, +0.437s
7. Patrick Heuzenroeder, Xcel Motorsport, +0.503s
8. Kanato Le, Hillspeed, +0.508s
9. Deagen Fairclough, Hitech TGR, +0.582s
10. Will Macintyre, Elite Motorsport, +0.582s
11. Dion Gowda, Xcel Motorsport, +0.600s
12. Keanu Al Alzhari, Hitech TGR, +0.628s
13. Noah Lisle, JHR Developments, +0.634s
14. Yuanpu Cui, Argenti with Prema, +0.639s
15. Reza Seewooruthun, Argenti with Prema, +0.671s
16. Hiyu Yamakoshi, Hillspeed, +0.854s
17. Nikita Johnson, Hitech TGR, +0.880s
18. Emerson Fittipaldi, Fortec Motorsports, +0.905s*
19. Jack Sherwood, Xcel Motorsport, +1.051s
20. Mika Abrahams, Fortec Motorsports, +1.088s
21. Hugo Schwarze, VRD Racing, +1.230s
22. CDR1, Chris Dittmann Racing, +1.292s*
23. Enzo Tarnvanichkul, VRD Racing, +1.459s
24. Flynn Jackes, Elite Motorsport, +1.642s
25. Stefan Bostandjiev, Fortec Motorsports, +1.666s
26. Bianca Bustamante, Elite Motorsport, +2.523s
27. Divy Nandan, Chris Dittmann Racing, +4.984s*
*Entry not yet placed for race weekend