A person familiar with the decision says Major League Baseball is closing all of its spring training sites over concerns about the coronavirus pandemic.
The person spoke Friday night on condition of anonymity because there was no official announcement.
Earlier in the day, the Philadelphia Phillies said five players tested positive for COVID-19 this week at the team's spring complex.
At least four teams in Florida and Arizona had already closed their camps.
The moves came while MLB owners and players try to negotiate a deal to start the season. They had hoped to begin a second round of spring training by next weekend.