DURHAM, N.C. -- Not only did No. 18 Duke have to overcome Clemson on Saturday afternoon, but the Blue Devils had to deal with human nature as well.

Two days after a showdown with its biggest rival, Duke didn't secure a 64-62 victory until Clemson's last possession went awry.

The game tested Duke's energy level because it came about 42 hours after conquering rival North Carolina in a much more charged-up environment Thursday night.

"What a 40 hours," Duke coach Mike Krzyzewski said. "You have to fight human nature. It's how much do you have in the tank?"

Barely enough as it turned out, partly because Luke Kennard went on a personal scoring spree after Clemson took a second-half lead at Cameron Indoor Stadium.

Clemson's Shelton Mitchell never really got much of a shot off as he looked for a 3-point launch at the buzzer after the Tigers gained possession with 6.2 seconds left.

"I knew he didn't have time to pass it," Duke guard Matt Jones said of the last sequence.

Kennard, a sophomore guard, scored 15 consecutive of his team's points across a second-half span of about eight minutes on his way to 25 points.

"Especially that stretch when we were having a hard time scoring," Jones said of Kennard's impact. "We needed him to give us a spark."

Jayson Tatum added nine points for Duke (20-5, 8-4 ACC), which won its fifth game in a row.

"This is our best win because we beat a good Clemson team and we (beat) human nature," Krzyzewski said.

Clemson shot 56.7 percent in the second half after only 17.9 percent in the first half.

"We defended as well as we have all year," Clemson coach Brad Brownell said of keeping within striking distance. "We got knocked down and kept getting back up."

Tatum's 3-pointer with just more than two minutes left gave the Blue Devils what appeared to be safe lead at 62-55. Clemson responded with the next five points before a pair of Kennard free throws at the 43.9-second mark. Marcquise Reed answered on a drive for Clemson.

After a Duke misfire, the Tigers regained possession with 6.2 seconds to play without a time-out. They had another chance to inbound with 4.3 seconds left near midcourt.

"I didn't want to call a time-out so (Brownell) could set something up," Krzyzewski said.

Shelton Mitchell's 23 points and Elijah Thomas' 15 points led Clemson (13-11, 3-9). Those were career-high totals for both sophomores.

It was the Tigers' sixth ACC loss by five points or less.

"Unfortunately, more of the same for us," Brownell said. "Our kids played their hearts out."

Clemson closed a 14-point deficit to 38-34 in the opening six minutes of the second half. The Tigers went ahead 45-44 on Reed's dunk off a Blue Devils turnover with 10:10 to play.

Kennard bagged 3-pointers on Duke's next two possessions.

Duke relied on defense in the first half for a 29-18 lead at the break. That marked the fewest points scored against the Blue Devils in any half this season.

"You really can't hold a team down like that (the whole game)," Tatum said.

It took more than 12 minutes for Duke to produce eight baskets, including six 3-pointers, for a 22-12 advantage. Seven of the Blue Devils' 10 first-half field goals were from outside the arc.

Clemson missed 15 of 17 shots during a first-half stretch of offensive misery. That was part of the Tigers' 17.9-percent shooting in the first half -- and they were 0 of 5 on 3-pointers.

Thomas scored the game's first four points, and Duke called a timeout 68 seconds into the game. Duke didn't score for the first 2 1/2 minutes.

NOTES: Duke holds a 108-31 series lead, though the teams had split their past four meetings. ... Clemson hasn't won at Duke since 1995. ... Clemson has reached the 80-point mark in nine games this season, its most at that level since the 2009-10 season. ... The Tigers had scored at least 25 points in every half this season until the first half Saturday. Four years ago in the same building, Clemson had 10 first-half points. ... Duke plays its first road game of the month with Wednesday night's visit to Virginia. ... Clemson's lone home outing during a four-game stretch comes Tuesday night against Wake Forest.