On Wednesday, NCAA president Mark Emmert believed college sports' governing body would still be able to stage men's and women's basketball tournaments without fans in attendance.

But over the next 18 hours or so, Emmert and other NCAA officials came to understand the growing coronavirus outbreak and its threat to student-athletes, coaches and other people who would be in attendance at tournament sites around the country. The NBA's suspending its season after Utah Jazz center Rudy Gobert tested positive for COVID-19 was the "exclamation point" for the NCAA, according to Emmert.

The board of governors, which consists of 20 members, including 14 university presidents, soon voted unanimously to cancel the basketball tournaments and other NCAA championships.

In a wide-ranging interview with ESPN on what was supposed to be Selection Sunday, Emmert said concerning medical reports, the lack of testing for student-athletes, coaches, their families and other personnel, and decisions made by state and local governments to curtail mass gatherings to try to contain the pandemic forced the NCAA to cancel the basketball tournaments and championship events for spring sports.

"We [were] completely convinced at 4 p.m. on Wednesday that we could conduct the championships without fans by controlling the sites effectively," Emmert said. "We thought we could control the perimeters and control the environment, and, as best as possible, travel, because it's mostly charter travel and buses one way or another. We felt really confident about it. We were feeling really, really good."

Emmert's hopes changed on Wednesday night, however, after Gobert became the first NBA player to test positive for COVID-19, which prompted the NBA to suspend its season. Two other NBA players have subsequently tested positive: Jazz guard Donovan Mitchell and Detroit Pistons forward Christian Wood, who matched up against Gobert in a March 7 game.

"It was like, 'Yeah, this is real,'" Emmert said.

Dan Gavitt, the NCAA's vice president for men's basketball, said Gobert's situation was a wake-up call for some players who were competing in conference tournaments, as well.

"When Rudy Gobert was infected on Wednesday night, I think the realization in the basketball community hit home and was very much felt on Thursday morning," Gavitt said. "The student-athletes, from what we were hearing and sensing, felt very vulnerable. Here was someone they would all like to be one day, playing in the NBA, who got infected and was quarantined with his teammates. His opponents were quarantined.

"That was really, in my opinion, a seminal moment in everybody's mindset about how impractical and possibly not responsible it would be at that point to go forward with trying to hold these national championships."

Emmert said another concern was that the NCAA wasn't convinced it could get enough testing kits and obtain results in a timely manner -- even if the basketball tournaments were reduced to only 16 teams.

"One of the big data points that changed was that we were really hopeful that we could access testing enough so that we could test our student-athletes and coaches and make sure that we were good there," Emmert said. "The communication started to come back that that may not be possible, that the testing protocols that were available were a little bit worse than we'd anticipated."

Emmert said using COVID-19 tests on otherwise healthy players and coaches was also an ethical dilemma.

"You're talking about a very limited resource -- these test kits," Emmert said. "I'm not a public health official, but you've got this very scarce resource right now. Whether it should be scarce or not is another question, but it is scarce. And here you're talking about otherwise really, really healthy people, and should you take that scarce resource and test otherwise [healthy] 19-year-olds? Some of the public health officials were saying that's not a best use of this resource, and we were not going to have access to what we thought we needed. That was just one data point."

Brian Hainline, the NCAA's chief medical officer and leader of its COVID-19 advisory panel, agreed that testing would have been one of the biggest hurdles the NCAA faced if it had decided to go forward with the tournaments.

Hainline also said he had conversations with two advisory board members who were physicians on staff at Emory University in Atlanta -- home of the Centers for Disease Control and Prevention and of this year's Final Four -- about creating the most "sterile environment" and having the two doctors oversee all the testing and the containment measures, with the CDC's blessing, so the NCAA could still put on an abbreviated tournament without fans. However, they soon realized that plan just wouldn't work given the myriad of potential issues the NCAA would have had with testing.

ESPN's Paula Lavigne contributed to this report.