The 11th-seed Wolfpack (24-12) will play Kansas on Friday in St. Louis after surviving a furious comeback by the Hoyas (24-9) that ended when Jason Clark's hurried three-point attempt from the right wing was off the mark at the buzzer.
"We pushed the ball up the court, tried to get a last shot," Clark said, his eyes brimming with tears. "I felt like it had a chance, but it didn't."
C.J. Williams, Scott Wood and C.J. Leslie each had 14 points, and Brown added 12 for N.C. State
The Wolfpack's defense spurred a 12-0 first-half run that included seven points by Williams and helped turn an eight-point deficit into a three-point halftime lead.
The Hoyas, riding the shooting of Hollis Thompson, who had 23 points, drew to 63-61 before freshman Otto Porter missed a 15-foot jumper under pressure with 14 seconds left.
Brown, a 74-percent shooter at the line, made two foul shots for a 65-61 lead. Clark, who finished with 10 points, then went the length of the court for a layup before Brown was fouled again with 4.6 seconds left. He hit the first but missed the second, and the Hoyas raced down court for a potential tying three.
"I was just praying it wasn't going in," Williams said.
Elijah Johnson had 18 points, including three three-pointers, and Thomas Robinson had 11 points and 13 rebounds to lead second-seeded Kansas (29-6) to a 63-60 win over Purdue in a Midwest Regional game in Omaha, Neb.
Robbie Hummel had 26 points for the 10th-ranked Boilermakers (22-13), who led 36-30 at the half.
Purdue led 60-57 with 2:02 left but the Jayhawks scored the game's final six points.
Tar Heels win
John Henson proved he's healthy enough to help North Carolina's latest push for the Final Four.
The junior had 13 points, 10 rebounds and four blocks in his firast game back after suffering a wrist injury, and the Tar Heels beat Creighton, 87-73, at Greensboro, N.C.
Kendall Marshall added 18 points and 11 assists for the top-seeded Tar Heels (31-5), who reached the Round of 16 for a record 25th time.
Doug McDermott scored 20 points for the eight-seeded Bluejays (29-6), who couldn't keep up with the hot-shooting Tar Heels.
Henson had missed the last three games after spraining his left wrist during the Atlantic Coast Conference Tournament when he fell after being fouled.