The New York Yankees were set to come out of the all-star break with a four-game series at home against the Boston Red Sox, but Thursday’s opener was postponed because of a coronavirus outbreak among the hosts.

Yankees General Manager Brian Cashman said that six of his players tested positive, three of whom were confirmed with the virus and were placed on MLB’s covid-19 injured list: pitchers Nestor Cortes Jr., Jonathan Loaisiga and Wandy Peralta. Three other Yankees players are awaiting lab results after rapid testing indicated they, too, had the virus; if confirmed, they will join their three teammates on the injured list.

According to ESPN, Boston’s Rafael Devers said Thursday that one of the Yankees who went to Denver for Tuesday’s All-Star Game had tested positive. Multiple outlets cited sources in reporting that the New York player is Aaron Judge, who was a starter in the game while teammates Gerrit Cole and Aroldis Chapman were reserves. If so, the Red Sox players who were also in Denver might not be the only ones asked to undergo additional testing, as reported by ESPN.

Red Sox Manager Alex Cora said he was “worried” about his team’s five all-stars: Devers, Xander Bogaerts, J.D. Martinez, Nathan Eovaldi and Matt Barnes.

“Some of them are vaccinated,” Cora said, “and some of them are not.”

Red Sox players took the field Thursday for batting practice, while the Yankees canceled their session in the cage.

Cashman said that Cortes, Loaisiga and Peralta were fully vaccinated, but he indicated that not all of the other three players were. The Yankees are among the majority of MLB teams that have hit the league’s goal of 85 percent vaccinated. The Red Sox are reportedly not among that group.

“We have a couple of them that have had symptoms, but for the most part, they’re doing pretty well,” Yankees Manager Aaron Boone said of his affected players. “We’ll just rally around them and give them the support they need and see where this thing goes as the hours unfold.”

It was not immediately clear when Thursday’s game would be made up or whether Friday’s scheduled game would be played. Cora said he hoped there would not be a doubleheader Friday.

“I think the most important thing is their clubhouse now,” he said. “I think we’re going to be aggressive as far as testing; we talked about it today. It doesn’t matter if you’re vaccinated or not. I think the smart thing to do is get back to what we did earlier in the season.”

Loaisiga tested positive while the Yankees were in Houston last weekend for a series against the Astros, and he stayed behind there to quarantine, Cashman said.

When the Yankees went through another coronavirus outbreak in May, it was limited to coaches and staff members, all of whom were fully vaccinated. Shortstop Gleyber Torres reportedly had a false positive at that time.

“The last year and a half has prepared you for this kind of stuff,” Boone said Thursday. “It’s certainly disappointing and frustrating. I don’t want to be sitting here talking about this. I desperately want us to go back to as normal as possible, but that’s out of our control. We’ve just got to do the best with the circumstances.”