Virginia Tech looked like it was ready to do something big.
The Hokies led No. 8 North Carolina 39-34 at halftime after a huge offensive surge from Dorenzo Hudson, whose 16-point first half reminded some that he once scored 41 in a game.
Then it all fell apart as the Tar Heels reeled off 19 straight points early in the second half and used a run that built to 31-5 to take command on their way to an 82-68 victory Thursday night.
"They just came out and punched us in the second half, and we didn't respond," said Erick Green, who led the Hokies with 17 points. He said the Hokies have to learn to play 40 minutes.
"We were with them in the first half, but we've got to learn to play two halves," he said. "That's a problem for us right now. ... That's been the story every time we've been losing."
The Hokies (11-7, 0-4 Atlantic Coast Conference) missed 15 straight shots during the run and lost their fourth straight. They are off to their first 0-4 start in league play since the 2006 team lost its first six.
Coach Seth Greenberg said much of what ails his team is inexperience.
"We're a young team that's a work in progress," he said. "There were some positive things to take out of it. It's real easy to be doom and gloom and have a bunch of negative energy, but that's not going to happen. No one said this was going to be easy. But I think we took a step forward. That team we played is a very good basketball team that played really well in the second half."
They also have Harrison Barnes, who scored nine of his 27 points during the 19-0 blitz.
John Henson had 16 points, 16 rebounds and six blocks for the Tar Heels (16-3, 3-1), who trailed 44-36 before Barnes started the run with two free throws, a jumper and a dunk. When it was over North Carolina led 67-49 with 8:23 remaining.
Dorenzo Hudson added 16 points for the Hokies all of them in a dazzling span of less than 8 minutes in the first half. Jarell Eddie added 15 points and freshman Robert Brown had 12.
The Tar Heels trailed 39-34 at halftime but took command quickly once Barnes heated up. His six consecutive points and two free throws by Tyler Zeller tied it at 44, and with the Hokies unable to make anything, Barnes added an 8-footer, Reggie Bullock hit a 3-pointer and Henson a foul-line jumper. A three-point play by Zeller and Barnes' free throw finished the burst that lasted 5 ½ minutes.
Dorian Finney-Smith's two free throws ended the Hokies' scoreless drought, but the Tar Heels scored seven more points before Brown's 3-pointer, Tech's first field goal in more than 9 minutes.
By then, the suspense was gone and both coaches substituted freely.
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