Boston Celtics guard Jaylen Brown has tested positive for COVID-19.

The team announced Brown's diagnosis Friday and said he is asymptomatic and quarantining.

Brown hasn't said whether he has been vaccinated. 

"I think it's a personal decision and have my own thoughts about it, but I respect my teammates' decision," he said during Celtics media day Sept. 27. "I know everyone has an opinion on it, but it's a personal choice."

Per an NBA memo that outlined protocols for the 2021-22 season (h/t ESPN's Tim Bontemps), vaccinated and unvaccinated players have different rules.

Unvaccinated players are required to undergo daily testing and lab-based testing on game days. They are also unable to dine indoors with teammates and other Tier 1 personnel and must remain six feet away from any other person. 

Vaccinated players only have to undergo testing if they are "symptomatic, are a close contact of someone who tests positive for COVID-19 or a team medical staff member of league physician requires it."

ESPN's Adrian Wojnarowski reported that 95 percent of players have been vaccinated as of Sept. 30.

The Celtics will play their second preseason game Saturday against the Toronto Raptors. Their regular-season opener will take place Oct. 20 against the New York Knicks at Madison Square Garden.