CLEMSON, S.C. -- Oh, no, not again.

North Carolina forward John Henson couldn't keep from flashing back to his team's second-half collapse at Duke last Wednesday night when Clemson overcame the Tar Heels' double-digit lead to move in front.

This time, though, North Carolina (No. 21 ESPN/USA Today, No. 20 AP) stood strong to hold off the Tigers for a 64-62 victory Saturday.

"I'm not going to lie to you, I was thinking about the game on Wednesday" when Clemson used an 8-0 run to start the second half and take its first lead, Henson said.

"But we fought back this time. We kept our composure," Henson continued. "I think that's just a lesson we learned from the Duke game."

Freshman Harrison Barnes scored 20 points, fellow frosh Kendall Marshall had 18 points and Henson collected his third straight double-double with 14 points and 12 rebounds.

The Tar Heels (18-6, 8-2 Atlantic Coast Conference) looked like they had the league lead as they took a 43-29 lead into the locker room at Cameron Indoor Stadium the other night.

Instead, Duke's experience won out in a 79-73 victory as North Carolina was held to just 30 points in the second half.

Against Clemson, North Carolina's youngest players showed they had learned something from that loss.

"I feel a lot better than I did Wednesday night," North Carolina coach Roy Williams said.

Barnes dunked with 3:01 left to put the Tar Heels ahead to stay, 53-51.

"When that happened, I said, 'OK, we're going to win this game,' " Marshall said. "It took the crowd out of it. Everything went silent. They didn't see it coming. We didn't see it coming."

Clemson senior Demontez Stitt might say the same of what happened soon after when Marshall stole the ball and made an easy layup for a 55-51 lead.

Barnes said he wasn't planning to dunk when he went up, but saw clean air and went for the one-handed jam.

"There's no question that play fired Harrison up, and also the rest of our team," Williams said.

The Tar Heels eventually built a 61-53 lead in the final minute before 3-pointers by Bryan Narcisse and Stitt in the last 10 seconds led to the final margin.

The Tar Heels have won six of their last seven this year and 12 of the past 13 against Clemson.

Clemson coach Brad Brownell couldn't fault his team's effort -- the Tigers outrebounded North Carolina 47-36 -- but regretted the missed opportunity.

He thought the Tar Heels' second-half struggles at Duke steeled them for Clemson's sold-out Littlejohn Coliseum.

"I'm not sure that that didn't help them a little bit, going through it once," the first-year coach said.

Stitt led the Tigers with 17 points, 13 in the second half, and sophomore Milton Jennings had 15 points and 12 rebounds.

Marshall, the Tar Heels' new point guard, ended with 18 points, including going 10 of 11 from the free throw line.

Jerai Grant, Clemson's a 6-foot-8 senior, was held scoreless as he missed all three shots. Grant, the Tigers' leading rebounder, came away with only one board.

Henson, the 6-10 sophomore, had a lot to do with Grant's troubles, adding four blocks in his eighth double-double this season.

The Tar Heels threatened to blow this one out with a 15-4 start and were still ahead 28-22 at halftime. However, Clemson got back into it with an 8-0 run to start the second half and lead 30-28. Neither team was up by more than four points until the final minute.

They hoped that effort wouldn't continue here at Littlejohn Coliseum. After all, the Tar Heels' last visit here wasn't a happy one. It started with the Tigers grabbing a 35-12 lead and ended with Clemson fans rushing the court after the 83-64 victory.

North Carolina made sure that didn't happen this time, Barnes getting the Heels off to the early lead. Barnes scored seven points, Henson added two baskets and Marshall drove in for an uncontested layup.

Clemson opened the game 2 of 15 from the field and went nearly 7 minutes with a bucket.

After a timeout and some fiery words from Brownell, the Tigers regrouped with a 14-4 run to tighten things up.

Still, North Carolina's defense kicked in near the end to keep in front. Clemson, tied with the Tar Heels for best shooting percentage in ACC games coming in, finished just 9 of 33 (27.3 percent) from the field and made just two of 15 3-pointers.

Stitt and Grant, Clemson's top two scorers who average better than 26 points a game, were a combined 2 of 9 for four points.