Freshman Alexis Jones scored a season-high 22 points and fifth-ranked Duke beat No. 15 North Carolina 65-58 on Sunday for its Atlantic Coast Conference-record 17th regular-season league victory.
Elizabeth Williams added 13 points for the Blue Devils (27-2, 17-1).
They overcame a season-high 29 turnovers by forcing the hot-and-cold Tar Heels (26-5, 14-4) to miss 19 consecutive shots during a span of roughly 10 minutes in the second half and beat their archrivals for the sixth straight time.
Tierra Ruffin-Pratt led North Carolina with 16 points on 5-of-23 shooting.
The Tar Heels got as close as six points in the final minutes, clawing to 50-44 when freshman Xylina McDaniel was fouled while making a layup with 3:03 left.
After she missed the free throw, Duke pulled away.
Jones raced downcourt to convert a three-point play and Richa Jackson followed that with a stickback with 2½ minutes left to push the Blue Devils' lead to 55-44.
North Carolina didn't get closer than seven the rest of the way.
Jones improved on her previous high of 15 points, set a week earlier in a win at Maryland, and now enters her first college postseason as one of the Blue Devils' on-the-floor leaders now that the team has lost do-it-all point guard Chelsea Gray to a season-ending knee injury.
Haley Peters added 10 points for Duke, which has already secured the No. 1 seed for the ACC tournament that begins later this week in Greensboro. The Blue Devils were the first to win 17 regular-season conference games because this is the first year of the ACC's 18-game league schedule.
Krista Gross finished with 10 points for North Carolina, which shot under 30 percent, had 22 turnovers and finished tied for second place with Maryland. The second and third seeds for the tournament were to be determined by a coin flip after all of the league's other tiebreakers couldn't separate the teams.
A win, of course, would have given that No. 2 seed to the Tar Heels, and it looked as though it might be headed that way when they went up 32-26 just over a minute into the second half on Brittany Rountree's 3-pointers.
But they went ice cold after that, missing everything but two free throws by Gross, while allowing Duke to take the lead and push it back into double figures.
Jones scored six points during the 22-2 run that put the Blue Devils back on top, with her highlight-reel finger-roll on a fast break coming one possession before Tricia Liston's 3 from the corner gave Duke a 48-34 lead.
Walteia Rolle ended the Tar Heels' cold spell with a stickback with just over 9 minutes left.
The Blue Devils — who won their 18th straight game at Cameron Indoor Stadium and haven't been beaten by an ACC team here in more than five years — had no trouble claiming the previous meeting, using a 29-3 run and leading by 33 in an 84-63 romp last month in Chapel Hill.
But, as Tar Heels coach Sylvia Hatchell pointed out, her team actually won the second half of that game — outscoring Duke 44-34.
They won the first half of the rematch, too.
The Tar Heels wiped out a 12-point deficit and took a six-point lead with a 22-4 run that started late in the first half and ended early in the second.
Ruffin-Pratt's jumper with 15 seconds left in the half put North Carolina up 27-26 — just the third time Duke trailed at the break.
They hit their first two shots of the second half to take that six-point lead — only to go remarkably cold after that.
Follow Joedy McCreary on Twitter at (at)joedyap.