Houston Rockets guard Russell Westbrook announced Monday that he was one of 19 NBA players to test positive for the novel coronavirus this month, delaying his availability for the league’s restart outside Orlando.

The NBA announced Monday that 19 players tested positive this month before 22 teams traveled to the protected Disney World campus, where games are slated to begin July 30. This new batch of positive tests follows the announcement of 25 positive tests during the first phase of the NBA’s testing program in June.

Only two of the 322 players who have arrived in Florida tested positive during their mandated quarantine period, the league said, and all positive cases are in isolation. The NBA did not identify which players tested positive in Florida but noted they never cleared the quarantine phase of the testing program and thus didn’t come into contact with their teammates, team employees or opponents.

Although the NBA doesn’t require teams or players to announce positive test results, citing privacy concerns, the 31-year-old Westbrook chose to reveal his. The nine-time all-star is not with the Rockets because he tested positive before the team traveled to join the Florida bubble last week.

“I tested positive for covid-19 prior to my [team’s] departure to Orlando,” Westbrook wrote on Twitter. “I’m currently feeling well, quarantined and looking forward to rejoining my teammates when I am cleared. Thank you all for the well wishes and continued support. Please take this virus seriously. Be safe. Mask up!”

James Harden, Houston’s leading scorer, has yet to arrive in Orlando, where the Rockets have emerged from a mandated quarantine period and have begun practicing. His health status remains unknown. Houston is set to play its first game July 31 against the Dallas Mavericks.

The NBA has strictly enforced its safety protocols, which aim to protect the players in Disney World from the outside world. Rockets forward Bruno Caboclo and Sacramento Kings center Richaun Holmes were forced to reenter an isolation period after violating quarantine guidelines. ESPN reported Caboclo left his room during his isolation period, noting he was unaware that he was not allowed to; Holmes announced on Twitter he had “briefly and accidentally crossed the NBA campus line” to pick up a food delivery.

Rockets Coach Mike D’Antoni downplayed the delayed arrivals of Harden and Westbrook, his two centerpieces, and declined to comment about their health.

“I think it will be fine,” D’Antoni told reporters. “They’ll be ready to go five-on-five when they get here. It will be nice having everybody in the game, but everyone’s dealing with [absences]. I don’t think by the time the eight games are over, there won’t be any effect. ... These are things that people are dealing with. We’re not going to get into why, why not. They’re on their way.”

When Westbrook and Harden arrive in Orlando, they will be subject to a two-day quarantine period and regular coronavirus testing.

Westbrook, who has averaged 27.5 points, 8.0 rebounds and 7.0 assists this season, is one of the highest-profile NBA stars to test positive for the coronavirus, which led the NBA to shut down its season March 11. The 2016-17 MVP joins Kevin Durant, Donovan Mitchell, Rudy Gobert and Malcolm Brogdon, among others, to have tested positive.

Multiple teams are waiting for players to arrive in Florida after positive tests, are dealing with roster fallout caused by positive tests or are coping without players who elected to skip the NBA’s restart for health reasons. Commissioner Adam Silver has said it would take a “significant spread” of the disease to delay or cancel his league’s planned restart, but he has resisted setting a specific threshold.