McAdoo finished with 14 points to lead the Tar Heels (23-7, 13-4 Atlantic Coast Conference), who blew a 14-point halftime lead and had to fight to the horn for their 12th straight win in their home finale. It is UNC's longest winning streak since 2008-09.
It marked the second straight close win for the Tar Heels against a team in the lower third of the ACC standings, following Saturday's 60-56 win at Virginia Tech. Still, they haven't lost since Jan. 20 heading into Saturday's finale at No. 4 Duke.
Atkins scored 21 points for Notre Dame (15-16, 6-12), which used a 22-5 run out of halftime to make a game of it.
McAdoo's basket started a 6-0 burst that gave UNC a 61-56 lead with 90 seconds left, but Pat Connaughton's three-point play cut the deficit back to two. Then, after Atkins' driving layup with 8.6 seconds left, Paige—shooting 89 percent from the free throw line on the season—made just 1 of 2 with 6.6 seconds left to give Notre Dame one more shot to tie or win.
Atkins drove into the paint against McAdoo and Paige, but Paige knocked the ball away and the horn sounded to end it.
Notre Dame, playing without senior center Garrick Sherman due to a hand injury, closed its regular season with two straight tough losses.
Connaughton had Notre Dame's first 10 points of the second half and finished 17 points and a season-high 13 rebounds.
Notre Dame led 56-55 with about 4 minutes left before Paige found a trailing McAdoo for the go-ahead basket. Then, after a turnover from Atkins, Brice Johnson scored inside to push the lead to three and fellow sophomore J.P. Tokoto hit a jumper to beat the shot clock for the 61-56 lead with 1:28 to play.
Tokoto finished with 11 points for UNC, which managed nine points through the first 14 minutes of the second half. Paige finished with just seven points on 2-for-8 shooting.
Notre Dame shot 54 percent from the field in the second half to erase the 41-27 halftime deficit.
Follow Aaron Beard on Twitter at http://www.twitter.com/aaronbeardap