North Carolina alternated between dominant and mistake-prone against its fiercest rival, flirting with both a blowout win and a crushing loss all in one half.

Still, the No. 14 Tar Heels were good enough to finish off their first regular-season sweep of No. 7 Duke in six years.

Diamond DeShields scored 18 points while fellow freshman Allisha Gray scored all 12 of her points after halftime in UNC's 64-60 win on Sunday, a game that saw the Tar Heels build a 19-point lead then nearly give away every bit of it before hanging on late.

Another freshman, Stephanie Mavunga , had 12 points and 11 rebounds for the Tar Heels (22-8, 10-6 Atlantic Coast Conference), who ended a two-game losing streak and earned their first sweep of the Blue Devils since the 2007-08 season.

Now they're headed to Greensboro for this week's league tournament under associate head coach Andrew Calder , who continues to lead the team while Hall of Fame coach Sylvia Hatchell is away focusing on treatment for leukemia.

"As you know, we're talented and we feel like we can beat anybody anywhere," Calder said. "We could struggle in some games, too. Right now we think we're getting ready to gel and we're going to take off."

His young squad ran off a 20-0 run spanning halftime to lead 50-31, then watched Duke (25-5, 12-4) respond with a 16-0 burst and fight back within a point.

Mavunga came up big, scoring on a stickback after Duke got within 53-52 on Ka'lia Johnson's three-point play. She then kicked out to Gray for a 3-pointer then scored inside off a feed from DeShields that pushed the lead back to 60-52 with 2:02 left. Duke never got it back to a one-possession game.

"We never really got down on ourselves whenever they started making their run because we knew we can stick together and we can overcome this," Mavunga said.

Tricia Liston scored 19 points despite battling back problems for the Blue Devils, though only four of those came after halftime. Johnson and Elizabeth Williams each scored 12 points for injury-depleted Duke, which had lost top point guards Chelsea Gray and Alexis Jones to season-ending knee injuries since January.

"We have to have consistency of our effort, fight, rebounding," Duke coach Joanne P. McCallie said. "There's some basics that have to happen. I think in that time that we were not as successful and they were, we weren't covering the basics. Stops, rebounds, fundamentals. Fundamentals are very important in March, for every team."

The Tar Heels won the first meeting on Feb. 10, with DeShields scoring 30 in UNC's first win in Duke's famously hostile Cameron Indoor Stadium since 2008.

But the Tar Heels had lost two straight games coming into this one, losing at home on a cold-shooting day to a Virginia Tech team with two league wins followed by Thursday's 25-point loss at No. 2 Notre Dame.

DeShields didn't shoot particularly well, going just 7 for 22 from the field this time around. But she hit a couple of big shots, including a tough jumper from the right wing to beat the shot clock with 1:09 left followed by a driving basket 27 seconds later that kept the Blue Devils at arm's distance.

She set the program's single-season freshman scoring record in the first half.

Duke got off to a fast start for a 13-3 lead, but bumbled away two straight turnovers that led to transition layups right before halftime to give UNC a 36-31 lead at the break.

Allisha Gray , who was limited to eight first-half minutes when she picked up two fouls, hit two of her four second-half 3-pointers to spark UNC's 14-0 run out of halftime. By the time DeShields hit a stepback jumper over Oderah Chidom and later a free throw, the Tar Heels led 50-31 with 16:11 left.

Yet the Blue Devils, who had been scoreless for 7½ minutes during UNC's run, answered with an equally impressive burst. That 16-0 spurt against the suddenly turnover-prone Tar Heels _ who at one point had turnovers on four straight possessions and went scoreless for 10 minutes _ helped them regroup to make a game of it.

The Blue Devils own the No. 2 seed in the 15-team ACC tournament and play in Friday's quarterfinals. The Tar Heels are the No. 6 seed and will play in Thursday's second round.