NBA players' mental health is reportedly viewed as the "most looming unknown" as the league attempts to resume its 2019-20 season in a "bubble" format at the Disney World complex in Orlando, Florida.

ESPN's Baxter Holmes reported Friday interviews with players, front office executives and team officials in charge of handling mental health revealed that aspect of the NBA's plan to play amid the coronavirus pandemic "could well determine the bubble's viability and success."

"Not being able to see your family, being there for three months, playing games with no fans—it's going to be mental," reigning NBA Most Valuable Player Giannis Antetokounmpo of the Milwaukee Bucks said. "You've got to push yourself through this."

The minimum time in Orlando, counting preparations before games restart, will be around 40 days if everything stays on schedule, while those who advance in the playoffs will stay progressively longer, per Holmes.

"It's tough," San Antonio Spurs guard DeMar DeRozan said. "You're taking guys that have been with their families every single day for the last few months and all of sudden, separating everybody into this one confined space and taking away a lot of joyful things we do outside of basketball. ... It'll be something for every single player when it comes to mental health."

NBA players are also relying on their counterparts and other members of the teams' traveling parties to follow all COVID-19 guidelines related to the bubble in order to avoid a widespread breakout.

Portland Trail Blazers guard Damian Lillard previously expressed doubt about everybody strictly adhering to the rules, according to Mark Medina of USA Today.

"My confidence ain't great because you're telling me you're going to have 22 teams full of players following all the rules?" Lillard said. "When we have 100 percent freedom, everybody don't follow all the rules. I don't have much confidence."

An unnamed NBA general manager told Holmes the league is asking a lot of players who usually have total freedom in their actions away from the team facility.

"The amount of pressure we're putting on those guys to live a life that they've never lived the entire time they've been in the NBA is just ridiculous," the GM said.

Meanwhile, coronavirus cases have been back on the rise in the United States in recent weeks, with Florida being one of the hotspots just as the NBA arrived to start their training camps. It places an even greater emphasis on following the rules.

NBPA director of mental health and wellness Dr. William Parham told Holmes he's hopeful the quarantine measures that have been in place since March will help players handle the bubble.

"As a team and as a unit, I suspect that [experience] is going to go into the bubble with them and they will find successful ways of navigating that space for however long they need to be there," he said.

The NBA schedule is set to resume July 30, and the last possible date for the NBA Finals is Oct. 13.