Ty Gibbs took the lead with 20 laps left at Charlotte Motor Speedway and stayed in front during a final restart for his second Xfinity Series victory of his rookie season.
Gibbs is the 18-year-old grandson of car owner Joe Gibbs.
Ty Gibbs had won at the Daytona road course three months ago. The racer took the lead after a side-by-side duel when leader Chase Briscoe lost control and spun out.
Austin Cindric was second and Harrison Burton third.
Daniel Hemric led the most laps at 105. But he was overtaken by Briscoe, then had a poor pitstop to fall behind.