CHAPEL HILL, N.C. (AP) -- Roy Williams wanted to make his players run sprints at halftime. The North Carolina coach settled for switching some of them to start the second half.
James Michael McAdoo scored 12 of his 14 points after halftime to help No. 19 North Carolina beat Northern Kentucky 75-60 in a lackluster effort on Friday night.
Marcus Paige and Leslie McDonald added 11 points each for the Tar Heels (9-3), who never trailed after opening the game with a 14-2 run.
''We were not very sharp, to say the least,'' Williams said. ''That was a huge part of the game. But at the same time, I didn't think we had the intensity and concentration level that we needed to have.''
With his team leading 35-30 at halftime, Williams changed his lineup. He surrounded Paige, the star point guard, with reserves Luke Davis, Isaiah Hicks, Jackson Simmons and Desmond Hubert.
The group responded with a 5-0 run, holding the Norse (4-8) scoreless on six possessions. Hubert had an emphatic blocked shot on Northern Kentucky's second possession, and the Tar Heels later delivered their best team defense of the game.
Northern Kentucky hunted for a shot before settling for an off-balance 3-pointer by Anthony Monaco just before the shot clock expired. The shot failed to draw iron, and the resulting violation sparked a standing ovation from North Carolina's fans.
As the reserves made good plays, including a highlight-worthy dunk by Hicks, Williams barked at his benched starters.
''I was ticked off,'' Williams said. ''I just wanted to try somebody different. I didn't know what it was. The assistants on my staff did a great job because what I wanted to do was stay out at halftime and run sprints the entire freaking half. They thought it was not the right thing to do. But, God, I wanted to do that so badly.''
Northern Kentucky trailed 44-37 early in the second half before North Carolina went on a 12-3 spurt to blow open the game.
McAdoo scored 10 points during the decisive stretch, making three shots inside and hitting four consecutive free throws.
''I took a couple of fadeaway shots in the first half, and that kind of played into their hands,'' he said. ''When I got the ball in the second half, I was just trying to attack.''
Tyler White scored 13 points to lead the Norse, whose three-game winning streak ended. Jalen Billups added 12 points, and Jack Flournoy and Jordan Jackson had 10 points apiece for Northern Kentucky, which shot 33 percent from the field, including 5 of 23 from 3-point range.
''I thought we had good shots and good opportunities,'' Northern Kentucky coach Dave Bezold said. ''They just weren't falling for whatever reason. But when you're playing a team with great length, it makes it pretty difficult.''
The Tar Heels hardly used their size advantage in the first half, frustrating their coach. North Carolina got outscored 16-12 inside before halftime.
That changed in the second half, when the Tar Heels outscored the Norse 14-12 inside and recorded 10 of their season-high 15 blocked shots.
''North Carolina did a great job of collapsing multiple people in the second half, and we didn't read it well enough to make an extra pass, an extra decision,'' Bezold said.
Northern Kentucky went more than 6 minutes before getting its first field goal of the second half, and the Tar Heels extended their lead to 12.
The Norse pulled within 44-37 on a 3-pointer by Monaco with 13:15 to play, but they never got closer.
The Tar Heels answered with seven straight points, six from McAdoo, to restore their double-digit lead.
''I feel like we definitely played a little on the lackadaisical side and tried to just think this was going to be a cakewalk,'' McAdoo said. ''Maybe for the first two or three minutes it was. But they competed well.''
Northern Kentucky started the game 1 of 13 from the field, and the Tar Heels pulled away as McDonald made three 3-pointers in a 3-minute stretch.
The Tar Heels had their biggest lead at 24-10 midway through the half before Northern Kentucky rallied behind White.
White scored on four drives into the lane and hit a 3-pointer in transition as the Norse scored on nine of 11 possessions.
Billups delivered a left-handed tip dunk to bring Northern Kentucky within 33-30 just before halftime.
P.J. Hairston, a swingman for whom North Carolina recently said it would not seek reinstatement, was not around. He watched the team's previous home games from the bench.
Williams would not say whether Hairston would be around the team in the future.
''I have no idea,'' Williams said. ''He's not on our team. I love him to death, but he's not on our team. I love him.''