After falling behind early, UNC returned to its regular starting lineup midway through the first quarter. But North Carolina's trusted rotation could do no better.
The Blue Devils ripped off a 27-6 run to close the second quarter, sinking seven 3-pointers and shooting 60 percent from the field in the half to secure a 53-22 advantage.
"That first half was basically a disaster ..." Coach Sylvia Hatchell said. "We just fell apart that second quarter."
The final two quarters brought little relief to the Tar Heels.
Duke went cold from the free-throw line and missed all five shots from beyond the arc. But the Blue Devils buried shot after shot, as North Carolina trailed by at least 30 points for all but 19 seconds of the second half.
Only one player — senior Marissa Riley, who converted her only attempt of the game — shot better than 50 percent from the field for UNC.
The loss marked the Tar Heels' fifth consecutive loss and their fifth straight defeat at the hands of Duke. But with the ACC Tournament three days away, North Carolina will attempt to regroup in time for a postseason run.
"It's a whole new season, and I want to see the team that beat Syracuse ..." Hatchell said. "I have not given up on this year."
"We try not to quit in the middle of the game, no matter what the scoreboard looks like. We just give it our all and then fix what we need to fix for this game so we can get ready for the next one." — first-year guard Stephanie Watts on the difficulty of facing an early deficit.
The Tar Heels celebrated senior day on Sunday, honoring eight players — including injured forward Xylina McDaniel and starters N'Dea Bryant and Hillary Summers. The seven active players combined to score 20 of UNC's 57 points.
Three numbers that matter
39: The Tar Heels trailed by 39 points early in the fourth quarter for their largest deficit of the season. The Blue Devils' 31-point halftime lead was also a season-worst for UNC.
12: UNC has now lost 12 of its last 14 games — all in conference — after winning its first two ACC contests. The Tar Heels' last win came on Feb. 11 against Virginia Tech.
25: With its loss to Duke, North Carolina has dropped 12 ACC games for the first time in 25 years. UNC went 2-12 in conference play in 1990-91, three years before winning the national championship.
The Tar Heels will travel to the Greensboro Coliseum for the first round of the ACC Tournament. UNC will play as the No. 13 seed against No. 12 Pittsburgh at 1 p.m. on Wednesday.