TAMPA, Fla. (AP) — A New York Yankees minor leaguer tested positive for the coronavirus, the Miami Marlins shut their spring training complex and baseball began bracing for the possibility that opening day could be delayed into May or longer.Major League Baseball was set to update teams Monday on its health policy in the wake of the virus outbreak.On Sunday, a Yankees prospect became the first known player affiliated with MLB to contract COVID-19. Yankees general manager Brian Cashman said a “younger player” was affected, without identifying him. Cashman said the player “feels much better” and his symptoms had subsided, but he was still isolated.“He did not have any interactions with our major league players,” Cashman said on a conference call.The Marlins, meanwhile, became the first organization to completely close their complex. Their big leaguers were told to take a break and avoid group activities.The Marlins' move was a team decision, rather than something mandated by MLB. But there were indications that other camps wouldn't stay open much longer, and more shutdowns could set off a chain reaction that would mean no real games for a while.MLB called off the rest of the spring training schedule on Thursday and said opening day, which had been scheduled for March 26, was postponed for at least two weeks.Teams and players agree that two to four weeks of additional spring training will be needed before the regular season begins. Given the time required to reopen camps, hold workouts and then get started, opening day appeared a long way off.Yankees player representative Zack Britton said Friday the team had voted to remain together in Tampa and continue voluntary workouts."I'm sure the numbers are going to change," Cashman said.Cashman said he met with the major leaguers Sunday in light of the positive virus case at the minor league complex across the street from George M. Steinbrenner Field and the "players didn't voice anything" as to their immediate plans. But he said as the players process the information, "I just suspect things are going to change."For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. The vast majority of people recover from the new virus within a few weeks.Some of Miami's players have homes near the spring training complex in Jupiter and plan to stay there. Others will go home.MLB and the union recently had given players the option to stay at the site of their spring camp, return to their offseason homes or go to the club's home city.Cashman said the player was tested on Friday morning and the minor league complex was closed. He said the positive result was confirmed late Saturday night into early Sunday morning.Cashman said no one else in the Yankees organization other than the affected minor leaguer had been tested for the virus.The team said the unidentified player had spent his entire time at the minor league complex and hadn't been over at the main stadium and facilities used by the major leaguers. Cashman said it was not known how or where the player contracted the virus.Cashman said the minor league complex has been shut through March 25 and some minor league players and personnel had been quarantined. He said both the major league and minor league complexes were undergoing thorough cleanings.The Yankees were on the east coast of Florida for an exhibition when MLB suspended the spring training schedule. Each day has seemingly brought new developments across the baseball landscape.“Sunday is radically different than where we were Thursday," Cashman said. ___More AP MLB: https://apnews.com/MLB and https://twitter.com/AP_Sports