Kyle Green |The Roanoke Times

Virginia Tech's Jarrett Boykin (right) fumbles the football as he's tackled by North Carolina's Charles Brown during the first quarter of Thursday's ACC game at Lane Stadium. The Tar Heels recovered the ball and converted the turnover into their first touchdown of the game.

Kyle Green |The Roanoke Times

Virginia Tech tailback Ryan Williams (middle) fumbles the ball in the fourth quarter of Thursday's game between the Hokies and North Carolina. The Tar Heels recovered, and went on to win.

Kyle Green |The Roanoke Times

North Carolina kicker Casey Barth is carried off of the field by his teammates after successfully kicking the game-winning field goal as time ran out at Virginia Tech.

Justin Cook | The Roanoke Times

The football flies out of the hands of Virginia Tech quarterback Tyrod Taylor after he had fallen into the end zone for a touchdown.

BLACKSBURG -- To think, Virginia Tech's football team thought it had a bad hangover after losing at Georgia Tech on Oct. 17.

Well, the one it wakes up with this morning will be doubly painful.

In a contest that most pundits thought they couldn't possibly lose, the 14th-ranked Hokies squandered numerous scoring opportunities and couldn't make critical defensive stops in the second half and lost 20-17 to North Carolina Thursday night at Lane Stadium.

Casey Barth's 21-yard field goal as time expired, set up by a fumble by Tech's Ryan Williams on the Hokies' 28-yard line with 2:02 to play left the crowd of 66,233 fans stunned. The 15-point underdog Tar Heels then raced onto the field in celebration for their first win in four ACC games.

Tech (5-3, 3-2 ACC) saw its already slim hopes for a third consecutive ACC title go completely down the tubes with it second consecutive conference loss.

After UNC (5-3, 1-3) tied the game at 17 on Barth's 19-yard field goal with 2:52 to play, the Hokies got the ball on their 24 in hopes of driving for a game-winning score. On third-and-6 from the 28, Williams took the handoff and had the ball knocked away by UNC defensive end Tydreke Powell. The ball was recovered by safety Deunta Williams, who returned it to the Tech 24.

"The guy hit the ball," said Williams, a standout redshirt freshman tailback who hadn't lost a fumble in his first 162 rushing attempts. "I really don't know what happened. But I know I lost the ball. What I can remember is I got hit, I'm not sure he hit the ball, and I tried to spin off it, and the ball came out.

"Personally, I feel like I kind of took the game away from us today. It was on the line and it was in my hands, and I fumbled. I feel like that's what cost us the game. I feel like [on] that drive, we would have moved it down the field and we would have scored, and we could have put the game away."

Instead, it was the visitors who put game away. UNC became only the second unranked ACC team to win at Lane. The other was North Carolina State in 2004, the Hokies' first season in the league. It was only UNC's third road win over a top-15 team in the past 30 seasons, its first since a 38-3 triumph at Clemson in 2001.

After Williams' fumble, the Tar Heels gave the ball six consecutive times to Ryan Houston. The Hokies called a timeout after the first two runs that gained seven yards. Houston then made the first down on third-and-4, allowing UNC to burn down the clock.

After three more Houston carries moved the ball to the 4, UNC stopped the clock with 2 seconds left. Barth, a sophomore, trotted on and then drilled the chip-shot field goal.

The Hokies went ahead for the first and last time at 17-14 on quarterback Tyrod Taylor's 1-yard touchdown run with 11:51 to play. However, Tech's defense couldn't stop a UNC offense that entered the game ranked among the nation's least productive units.

The Tar Heels converted a pair of third-down conversions, plus a critical fourth-and-7, when QB T.J. Yates found Greg Little for a 19-yard pass play to the Hokies' 17. The 78-yard drive, against a Bud Foster defense that knew the game was on the line, consumed 8:59 and 16 plays. Linebacker Cody Grimm was beaten on the play.

"That Virginia Tech defense, we're known for coming and playing tough ball and getting teams off the field in third-down situations," Hokies cornerback Rashad Carmichael said. "When you can't get a team off the field on third down, it's very frustrating."

Carmichael was beaten on the only score of the first half, a 13-yard TD pass from Yates to Jheranie Boyd with 2:44 left in the second quarter.

"I still don't know how he got that throw in there on me in the end zone," Carmichael said. "I didn't even see the ball. I looked back for the ball, but I still didn't see it. He threw a perfect pass. .... That's going to haunt me for a long time."

The Hokies trudged off the field down 7-0 at halftime to some boos from the faithful. The first-half doughnut on the scoreboard marked the first time Tech had been blanked in the opening 30 minutes of a game since 2007 at LSU. Tech had the ball inside the UNC 40 on five possessions, but failed to scratch, primarily because they were 2-for-8 on third-down conversions.

"I think it was bad execution," said Taylor, who was 11-for-23 passing for 161 yards. "We didn't take advantage of the opportunities that were given to us. It's something we've gotta learn from.

An interception by Carmichael set up Taylor 1-yard run that put Tech ahead.

"Tough loss. Real tough loss," Carmichael said.