Richard Cooper was back on the top step of the podium after fending off a charging Tom Booth-Amos for the Brands Hatch Sprint win.
The BPE Yamaha rider hit the front on the opening lap and took charge of the race as behind, the battle raged.
As polesitter Rhys Irwin dropped back down the order, Australia’s Tom Toparis moved up to second but dropped to third a few laps in when Booth-Amos passed him.
From there, the Gearlink Kawasaki rider set off after Cooper, pressuring him through the closing laps before making a couple of lunges on the final lap which didn’t pay off, although he was able to hold onto second as Cooper crossed the line 1.069secs ahead.
Toparis finished the race third to give the Macadam Racing team another podium, with Dutchman Jaimie van Sikkelerus fourth and Irwin fifth.
Harvey Claridge crossed the line eighth to claim GP2 class honours, with Cameron Fraser second in class and Harry Rowlings third.
Quattro Group British Supersport and GP2 Championships, Sprint result:
1. Richard Cooper (BPE Yamaha)
2. Tom Booth-Amos (Gearlink Kawasaki) +1.069s
3. Tom Toparis (Macadam Racing) +1.366s
4. Jaimie van Sikkelerus (MPM Routz Racing Team) +5.368s
5. Rhys Irwin (Astro-JJR Suzuki) +7.846s