Greensboro, N.C. ? Harrison Barnes ignored all the doubters, the questions about his game, even the bumpier-than-expected start to his career at North Carolina.

Those days felt long ago Saturday as the freshman put on a record-setting show that helped the sixth-ranked Tar Heels escape once again at the Atlantic Coast Conference tournament.

Barnes set a freshman tournament record with 40 points to help North Carolina rally past Clemson, 92-87 in overtime, in the semifinals, sending the Tar Heels back to the championship game for the first time in three years.

Barnes hit the go-ahead three-pointer with 4:13 left as part of a 9-0 spurt to open the extra period for top-seeded North Carolina (26-6), which continued its living-dangerously run in Greensboro with another big comeback. A day after rallying from 19 down in the final 10 minutes to beat Miami, the Tar Heels trailed the Tigers (21-11) by 14 in the first half and rallied from seven down in the final four minutes of regulation to force overtime.

“My goal was to be in the final,” Barnes said. “This is not how I imagined us doing it, but we find a way.”

The Tar Heels have won 19 of 21 games since losing to Texas on a last-second shot in December here. They’re now a win away from their 18th ACC tournament title, which would tie Duke for most all-time. They’ll face the fifth-ranked Blue Devils in today’s final, marking the first time the fierce rivals have met for the title in 10 years.