The Tar Heels (59-11) advance to face UCLA (45-17) at 8 p.m. ET on Friday. The Bruins are undefeated in Omaha.
North Carolina left-hander Hobbs Johnson allowed five hits in 8 1/3 shutout innings and third baseman Colin Moran went 3-for-4 with two RBIs for the Tar Heels, who scored five runs in the final two innings to turn a two-run lead into an insurmountable one.
Moran was the No. 6 overall pick by the Marlins in the 2013 First-Year Player Draft, while Johnson was selected by the Brewers in the 14th round.
"Tonight was all about Hobbs, just an incredible performance," North Carolina coach Mike Fox said. "He gave us exactly what we needed."
Johnson was backed in the middle innings by a play at the plate in the fourth and Moran's fifth-inning RBI single. With the way Johnson was throwing, the game seemed to be North Carolina's as soon as the Tar Heels scored their first run.
The 5-foot-11, 210-pound lefty was masterful once he got the lead -- and especially so after getting out of a two-on, two-out jam in the fourth. Johnson, who said all 132 pitches he threw were fastballs, retired 10 straight at one point and only four N.C. State baserunners got into scoring position.
Johnson lasted until the ninth, when Chris McCue closed the game thanks to a double play to right fielder Skye Bolt, who nabbed N.C. State's Brett Williams at first.
"Every single pitch [Johnson] threw was a fastball," said North Carolina catcher Brian Holberton, the Astros' ninth-round pick. "We just went right after them and wanted them to put the ball in play and let our defense work."
N.C. State lefty Carlos Rodon -- starting after a 108-pitch, complete-game win over the Tar Heels on Sunday -- dueled with Johnson until the fourth, when the game's first run scored by mere inches.
Moran led off with a single, Rodon threw Holberton's bunt into center field and first baseman Cody Stubbs (Royals' eighth-round pick) walked to load the bases. After Rodon induced a fielder's-choice groundout, Tar Heels shortstop Michael Russell lifted a fly ball to right field.
N.C. State's Jake Fincher settled under the ball, caught it and fired to the plate. Catcher Brett Austin received Fincher's throw just as Holberton was sliding head-first into home and the Tar Heels catcher managed to get his hand under Austin and touch the plate -- narrowly beating the throw.
"I don't think he even touched me," Holberton said. "I didn't feel anything on my back or anything. I was glad that he called me safe."
Austin spiked his helmet in disgust, Rodon displayed his displeasure and N.C. State coach Elliott Avent argued the bang-bang call to no avail.
"The ball just beat him so much that maybe we didn't block the plate good enough," said Avent, noting college baseball's rules against blocking the plate. "I don't know whether he got it right or not."
TV replays showed the correct call was made.
The close call eventually proved moot as the Tar Heels got to the Wolfpack bullpen late. North Carolina's late-inning offense also somewhat overshadowed Rodon's gutsy performance on three days' rest. The lefty allowed two runs (one earned) on four hits in five innings, striking out six while throwing 80 pitches.
"He was really, really good," said Avent, whose team finishes 50-16. "We thought it was going to be a 2-0 game until the eighth or ninth and we thought we'd have another comeback where we'd win it. The eighth unravelled us."
No. 1 North Carolina 7, North Carolina State 0
Mississippi State vs. No. 3 Oregon State, 3 p.m.
UCLA vs. No. 1 North Carolina, 8 p.m.