Freshman Harrison Barnes' 3-pointer from the top of the key with 3 seconds to play gave No. 13 North Carolina a 72-70 victory at Florida State on Wednesday night.
John Henson had 19 points and 12 rebounds and Barnes added 18 points for the Tar Heels (23-6, 13-2 Atlantic Coast Conference), who won their sixth straight game overall and their fifth in a row on Florida State's court.
North Carolina took the lead midway through the second half and was up 67-60 on Kendall Marshall's 3-pointer with 3:59 left. Florida State rallied to take a 70-69 lead with 18 seconds left on two free throws by Derwin Kitchen, who led the Seminoles (20-9, 10-5) with 13 points.
Florida State turned the ball over before getting off a final shot after Barnes' game-winner.
The Tar Heels can clinch the top seed in next week's ACC tournament win a win over No. 4 Duke on Saturday.
Leslie McDonald added 10 points for North Carolina, including two 3-pointers 43 seconds apart that gave the Tar Heels a 49-44 lead with 14:18 left.
Michael Snaer added 11 points and Bernard James had 10 for the Seminoles, who were without top scorer Chris Singleton (broken right foot) for the fourth straight game.
Florida State led 38-37 after a first half that saw both teams shoot 16 of 31 from the field and had nine lead changes and nine ties.
Henson, a 6-foot-10 sophomore from Tampa, had a big first half with 12 points, six rebounds and three blocked shots while Florida State answered with strong play from its bench players, who outscored the Tar Heel reserves 20-5.
North Carolina shot 47.3 percent for the game and had a 39-28 rebound advantage.
One of those Seminole backups, freshman Ian Miller, nailed a 3-pointer from the corner midway through the first half that gave Florida State its largest lead of the game at 26-19.
Florida State was attempting to finish a perfect ACC season at home for the first time since coming into the conference for the 1991-92 season.
Barnes had 17 points and 10 rebounds in the Tar Heels' 89-69 home victory over Florida State 24 days ago.