RALEIGH, N.C. (AP) -- Third-ranked Clemson didn't show its high-scoring form for much of Thursday night's trip to North Carolina State. While the Tigers were still good enough to stay unbeaten, it left them trying to figure out what was wrong afterward.
Clemson didn't score its first touchdown until late in the first half and didn't build a comfortable lead until early in the fourth quarter of a 26-14 win, though the Tigers took advantage of a critical third-quarter sequence to seize momentum.
Clemson came in averaging 45 points and 490 yards, but finished with 415 yards in its lowest scoring performance of the young season.
''It just wasn't smooth,'' said quarterback Tajh Boyd, who threw three touchdown passes. ''I don't really know if it was anxiety or having 12 days off or it just wasn't as rhythmful as we wanted it to be. Then, we came back in the second half and did some great things.''
Boyd's 30-yard scoring pass to Martavis Bryant capped the game-turning sequence - including an apparent Wolfpack touchdown negated by an official's whistle - that put the Tigers (3-0, 1-0 ACC) in control. Boyd found Bryant for another touchdown, with Bryant snatching the ball from defender Niles Clark for a 15-yard score that made it a three-possession game early in the fourth.
Boyd threw for 244 yards on 24-for-37 passing, with his first scoring toss coming on an 11-yarder to Sam Cooper with 2:23 left in the second that gave the Tigers a 13-7 halftime lead.
''Tajh is a perfectionist. That's the way he is in practice,'' Clemson coach Dabo Swinney said. ''That's the way he is all the time. He can't stand when he feels like he made a mistake. I just told him, 'Go to the next play.' I told (offensive coordinator Chad Morris), 'Just keep calling the game. We'll get him going.'''
Shadrach Thornton scored the Wolfpack's first touchdown on a 21-yard run in the second for a 7-6 lead, but N.C. State (2-1, 0-1) couldn't complete the upset in coach Dave Doeren's first league game.
''It's not a moral victory by any means,'' Doeren said. ''We do not accept losing here. But I'm proud of the way we competed.''
The Tigers entered Raleigh with their highest ranking in 25 years and a prime spot in the national championship chase. They also came in with memories of their inexplicably bad performance here two seasons earlier, when the Wolfpack scored 27 second-quarter points en route to a 37-13 rout of the then-No. 7 Tigers.
N.C. State followed that win with an upset of No. 3 Florida State here last year. But N.C. State's hopes of beating a top-10 team at home for the third straight season essentially ended in one frustrating sequence.
Receiver Bryan Underwood sprinted around the right side for what appeared to be an 83-yard touchdown to tie the game at 13 midway through the third. But officials ruled Underwood stepped on the sideline at the Clemson 47 and blew the play dead, making it an unreviewable play - replays appeared to show him remaining inbounds - that led to boos raining down from the Carter-Finley Stadium stands.
''It was right in front of me,'' Doeren said. ''He didn't go out of bounds. Unfortunately they blew it dead so they couldn't review it. It's an unfortunate deal. I know the guy felt bad about it. You can't do anything about it. That's just the way it is.''
Three plays later, Clemson's Vic Beasley knocked the ball loose from Pete Thomas on a sack for a fumble recovered by Spencer Shuey. The Tigers pounced on the opportunity, with Boyd hitting Bryant for the 30-yard score that made it 20-7 with 5:25 left in the quarter.
Bryant's impressive grab for his second touchdown on Clemson's next drive made it 26-7 with 11:27 left - and the booing over the Underwood call continued.
''It hurts, but hey, things happen in games,'' Underwood said. ''So you've got to bounce back with them, good or bad.''
N.C. State finished with 378 total yards, but failed to convert its first eight third-down tries and finished 3 for 16 for the game.
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