The positive test came back after Wednesday's game.
The team had a scheduled game with No. 15 Florida State in the ACC quarterfinals at 6:30 p.m. on Thursday after beating Louisville 70-56 on Wednesday night.
💔— Duke Men’s Basketball (@DukeMBB) March 11, 2021
That game was canceled. With the cancelation, Florida State advances to the ACC Tournament semifinals and will play the winner of Thursday's North Carolina vs. Virginia Tech game that will now be played at 8:30 p.m. on ESPN.
"Unfortunately, after going an entire season with no positive COVID-19 tests among our men's basketball student-athletes and coaching staff, one member of our program tested positive following Wednesday's ACC Tournament game in Greensboro," Kevin White, Duke University Vice President & Director of Athletics, said.
"I feel deeply for our players, who have done a terrific job all season in taking care of each other and the team," head coach Mike Krzyzewski said in a statement. "I am extremely proud of their collective attitudes and effort, which could not have been stronger. We are disappointed we cannot keep fighting together as a group after two outstanding days in Greensboro. This season was a challenge for every team across the country and as we have seen over and over, this global pandemic is very cruel and is not yet over. As many safeguards as we implemented, no one is immune to this terrible virus."
The decision ends the Blue Devils' streak of 24 consecutive NCAA appearances that began in 1996.
"Since last March when the pandemic started, we have listened to our medical experts and always put safety at the forefront of any determinations regarding competition," White said. "As a result, this will end our 2020-21 season. We wish every team still playing college basketball good health and the very best during the next few weeks."
The Blue Devils finished 13-11, 9-9 in the ACC.
"We have not asked more of any team in our history, and they deserve enormous credit for handling everything like the outstanding young men they are," head coach Mike Krzyzewski said in a statement. "I feel deeply for our players, who have done a terrific job all season in taking care of each other and the team. I am extremely proud of their collective attitudes and effort, which could not have been stronger."
Duke hadn't missed the NCAA tournament since the 1994-95 season when Krzyzewski stepped away from coaching following complications from back surgery. Assistant Pete Gaudet took over, with that team finishing 13-18 a year after Duke had played in the NCAA title game.
Before that, Krzyzewski had missed the tournament at Duke only in his first three seasons, when he went a combined 38-47 and faced growing pressure to turn things around as Triangle neighbors North Carolina (1982) and North Carolina State (1983) both won NCAA championships.
The first tournament bid came in 1984 and Duke went on to win 37 games while reaching an NCAA final two years later. That was the first in a remarkable run of seven Final Fours in nine years that included championships in 1991 and 1992. Krzyzewski's teams went on to claim three more titles in 2001, 2010 and 2015.
This year opened with some of the same expectations despite a young roster lacking the same NBA-ready talent of recent years with names like Zion Williamson and Jayson Tatum.
The Blue Devils started the year at No. 9 in the AP Top 25 but were unranked by mid-January for the first time in nearly five years. They lacked the typically rowdy homecourt edge in a fan-less Cameron Indoor Stadium and saw top freshman Jalen Johnson depart the team in February to prepare for the NBA draft.
"We as a program need to keep learning ... and keep appreciating what it takes to takes to win," Krzyzewski said. "You don't do that by not working hard or trying to get better. And that's what we're going to do."
The Associated Press contributed.