Elite Motorsport's Finn Harrison claimed his first GB4 race win in a dramatic final contest at Silverstone.
The British driver finished four seconds clear of Fortec's Jack Taylor, with Fox Motorsport's Branden Templeton third after holding off a charge from race two winner Lucas Blakeley.
There was drama before the race began, as pole sitter Ava Dobson's car jumped forward on the grid, leading to a delayed start. A new green flag lap was required, but the field set off at racing speed, and the race red flagged due to the confusion.
With a reduced 16-minute duration, the race finally got underway, and while Dobson, who had recovered her starting position stalled again, second place starter Megan Bruce took the lead, as Harrison held off Taylor through Maggotts and Becketts.
From defence to attack, Harrison went around the outside of Bruce at Stowe, and then pulled away, as Taylor also found his way past Bruce to move into second.
But the race was soon neutralised with Arden's Leon Wilson and Callum Baxter colliding at Luffield at the end of the first lap, with both retiring. Before the safety car was called, Templeton had moved past teammate Bruce to take third.
Racing resumed at the end of lap four, and Harrison immediately built a lead, taking the flag at the end of lap seven with a four second margin to Taylor, who secured a first podium despite heavy pressure from Templeton, who stood on the podium once more with third.
KMR Sport's Lucas Blakeley went from 11th to fourth, and was only a tenth of a second away from another rostrum, fighting past teammate Chloe Grant on the penultimate lap.
Grant settled for fifth, with Harry Burgoyne completing a KMR 4-5-6. Alisha Palmowski battled hard for Elite Motorsport and took seventh, with championship leader Linus Granfors eighth from 12th on the grid. Bruce and Fortec's Dan Hickey completed the top-10, with Dobson the final finisher.
GB4 Championship, partnered by the BRDC, Silverstone race three provisional result:
1. Finn Harrison, Elite Motorsport
2. Jack Taylor, Fortec Motorsport, +4.018s
3. Branden Templeton, Fox Motorsport, +4.703s
4. Lucas Blakeley, KMR Sport, +4.816s
5. Chloe Grant, KMR Sport, +5.944s
6. Harry Burgoyne, KMR Sport, +7.727s
7. Alisha Palmowski, Elite Motorsport, +8.745s
8. Linus Granfors, Fortec Motorsport, +9.598s
9. Megan Bruce, Fox Motorsport, +11.343s
10. Dan Hickey, Fortec Motorsport, +12.513s
11. Ava Dobson, VRD Racing, +12.842s
DNF. Leon Wilson, Arden Motorsport
DNF. Callum Baxter, Graham Brunton Racing