Kon Knueppel scored 17 points and No. 1 Duke held off a furious second half rally by rival North Carolina to beat the Tar Heels for the third time this season, 74-71 on Friday night to reach the Atlantic Coast Conference Tournament championship game.

Duke basketball and UNC played a thriller in the ACC Tournament at Spectrum Center. Here are the observations.

CHARLOTTE - Kon Knueppel scored 17 points and No. 1 Duke, playing without star freshman Cooper Flagg, held on after building a 24-point lead, beating North Carolina 74-71 in the Atlantic Coast Conference tournament semifinals on Friday night.

North Carolina just blew its shot at the ACC Tournament championship game in perhaps the worst way possible. With just 4.1 seconds left in the semifinal matchup against No. 1 seed Duke on Friday, UNC was called for a lane violation on a potential game-tying free throw.

North Carolina's furious comeback against Duke in the ACC Tournament semifinals came up short after Jae'lyn Withers committed a lane violation on teammate Ven-Allen Lubin's successful second free throw attempt — which had it counted,

Friday had all the makings of a classic win for UNC in a season that can best be described as a disappointment. Then Jae'Lyn Withers stepped over the line — literally. The Tar Heels lost a game-tying free throw against rival Duke,