The number of confirmed coronavirus cases in the NBA continues to grow, as the Boston Celtics guard Marcus Smart announced on Thursday that he has tested positive for COVID-19. The tweet came shortly after the Celtics released a statement saying that one of their players had contracted the coronavirus.

Smart said that he has been in isolation since getting tested five days ago, and stressed the seriousness of the virus.

“I’m OK, I feel fine. I don’t feel any of the symptoms,” Smart said in the video accompanying his tweet. “But I can’t stress enough practicing social distancing, and really keep yourself away from a large group of people — just really washing your hands and help protect yourself, and help protect others by protecting yourself.”

More details from the Celtics:

“The Boston Celtics learned today that a player has tested positive for COVID-19. Testing was initiated because of exposure to a known positive case. The Celtics player, who is not exhibiting symptoms, has been in isolation for several days and will continue to do so while being monitored by team medical staff. The team is awaiting further testing results and will communicate them as appropriate. Taking steps to maintain the health and safety of everyone in our organization and across the NBA remains our top priority, and we will continue to work closely with health officials and the league in addressing this situation.”

The Celtics become the seventh NBA team to have confirmed cases of the coronavirus, joining the Utah Jazz, Detroit Pistons, Brooklyn Nets, Denver Nuggets, Philadelphia 76ers and Los Angeles Lakers. Smart is the 14th NBA individual to test positive and the fifth identified player, along with Rudy Gobert, Donovan Mitchell, Christian Wood and Kevin Durant.