The Portland Trail Blazers have closed their facility for deep cleaning after three positive COVID-19 tests came back in a span of four days.

Sunday was to have been the first full day of training camp for the Blazers. They, along with all other NBA teams, began having players back in their facility for individual workouts last week. The team did not say if the positive tests involved players, staff or some combination of the two.

Portland is scheduled to open its preseason slate at home Friday against Sacramento, a game that — for now — is set to be televised nationally on ESPN.

Blazers President Neil Olshey, in a statement distributed by the team, said the decision to close the facility was made “out of an abundance of caution.” The team has also completed contact tracing, Olshey said.

The Blazers did not say how long their facility would be closed. There was no immediate announcement about the team’s plan for practice Monday, or if any talks had taken place about postponing or canceling Friday’s preseason opener.

“It’s something you’ve got to deal with,” Miami Heat guard and National Basketball Players Association vice president Andre Iguodala said Sunday when told of the Blazers’ situation — the first facility shutdown in the league since teams began gathering last week. “Hope for the best but prepare for the worst and see what happens from there.”

The league told its teams on Saturday that clubs found to not be complying with league rules designed to minimize the spread of the coronavirus this season could face major penalties such as forfeiting games or draft picks.

NBA teams began coronavirus testing to prepare for camp around Nov. 24, and the league said 48 players — almost 9% of all tested — were positive for COVID-19 in the first week of that program.