Rhys Irwin continued to shine as the Brands Hatch weekend fired into action, leading the way after first practice.
The Astro-JJR Suzuki rider clocked a 1min 29.032sec lap to beat Oxford Products Racing Ducati’s Ben Currie by a slim 0.054secs.
Third quickest was championship leader Tom Booth-Amos, who crossed the line a further 0.257secs behind Currie as Richard Cooper, back on the Russell Racing Yamaha this weekend was fourth with Tom Toparis fifth.
In GP2, it was Cameron Fraser who led the way, with Harvey Claridge second and Harry Rowlings third.
Quattro Group British Supersport & British GP2 Championships, FP1 result:
1. Rhys Irwin (Astro-JJR Suzuki) 1min 29.032s
2. Ben Currie (Oxford Products Racing Ducati) +0.054s
3. Tom Booth-Amos (Gearlink Kawasaki) +0.257s
4. Richard Cooper (Russell Racing) +0.318s
5. Tom Toparis (Macadam Racing) +0.413s