Carter Brown held off his MLav VisionTrack Academy team-mate Johnny Garness to take the first victory of the weekend by a mere 0.024s.
After starting from pole, Garness had to settle for second after another hard-fought scrap featuring almost a dozen frontrunners.
Third was Harrison Dessoy, just ahead of Ryan Hitchcock as Sullivan Mounsey crossed the line fifth.
Honda British Talent Cup, Donington Park, Race One:
1. Carter Brown, MLav VisionTrack Academy
2. Johnny Garness, MLav VisionTrack Academy +0.024s
3. Harrison Dessoy, Microlise Cresswell Racing/Eastern Garage Racing +0.443
4. Ryan Hitchcock, City Lifting by RS Racing +01.024
5. Sullivan Mounsey, Wilson Racing/J&S Accessories +1.024s