Blaney went from last to first to earn his fifth career Xfinity race win. It was his first victory on the circuit since the 2015 season at Kentucky, a span of 14 races without a win.
Harvick's tough luck at Charlotte continued. He has won 46 career Xfinity Series races, but has been shut out at Charlotte.
Blaney had qualified third for the race, but was sent to the back of the field to start the race because of unapproved tire changes to his No. 12 Ford. He raced to the lead early in Stage 2 — and won it —but needed a late restart to take the race.
Austin Dillon finished third and Christopher Bell fourth.