RALEIGH — Orwin Smith rushed for three touchdowns and No. 21 Georgia Tech beat North CarolinaState 45-35 on Saturday to extend its best start in more than 20 years.

Smith finished with 74 yards and scored on runs of 13, 9 and 3 yards to help the Yellow Jackets (5-0, 2-0 ACC) open with five wins for the first time since their national championship season in 1990.

Georgia Tech led 21-0, briefly allowed N.C. State to make a game of it in the third quarter and pulled away with three touchdowns in a 2-minute, 22-second span of the fourth.

Mike Glennon was 20 of 29 for 163 yards with touchdown passes covering 9 yards to Jay Smith and 1 yard to Tyler Purvis. The Wolfpack (2-3, 0-2) remained winless against Bowl Subdivision teams.

Tevin Washington completed just four passes for Georgia Tech — but two were touchdowns, covering 9 yards to David Sims and 38 yards to Roddy Jones. Isaiah Johnson returned an interception 34 yards for a score to help the Yellow Jackets pull away.

James Washington, starting for the injured Curtis Underwood, rushed for a career-high 131 yards for the Wolfpack. His 46-yard touchdown run got N.C. State within a score, down 21-14.

That’s when Georgia Tech used a scoring flurry befitting the nation’s most productive offense to take a huge lead.

Smith closed a 13-play drive that demoralized N.C. State by taking a pitch from Tevin Washington around right end and diving across the goal line with 12:29 left.

On N.C. State’s next offensive play, Johnson picked off Glennon’s pass and returned it for a score, and Tevin Washington found Jones deep for a TD that made it 42-14 with 10:07 remaining.

N.C. State made things interesting with two touchdowns in the final 34 seconds, including Brandan Bishop’s 33-yard return of Synjyn Days’ fumble with 20 seconds left to finish the scoring.

Glennon made it 21-7 with 1:15 left in the half on his scoring pass to Smith, and N.C. State got within a score on Washington’s long touchdown run on its first play of the second half.

That came after it looked as though the Yellow Jackets would have their way against an N.C. State team that entered with one of the worst — and most injury-riddled — defenses in the ACC. The Wolfpack, who started their third different combination of defensive linemen in five games, entered ranked 10th or worse in the ACC in three major defensive stat categories.

Smith capped each of Georgia Tech’s first two drives with touchdown runs. Four plays after Jemea Thomas took a snap on a fake punt and rumbled 27 yards for a first down, Smith took a pitch through the right side and ran 13 yards for a score.

Then, he made it 14-0 with 3:34 left in the first quarter when he took a handoff 9 yards for his second touchdown. At that point, he had touched the ball 27 times on offense this season — and had scored seven touchdowns.

Washington then made it 21-0 with his short flip to Sims on the first play of the second quarter, giving Georgia Tech a 173-30 advantage in total yards.