A PWHL playoff game is being postponed by the league “due to player safety concerns related to illness.”

Game 5 of the opening-round series between the Minnesota Frost and Montreal Victoire was supposed to take place on Monday in a winner-take-all semifinal showdown that will now have to be rescheduled.

The PWHL said in its announcement that medical assessment had ruled that the symptoms “are not consistent” with Hantavirus, though the league didn’t say who is ill. 

“The decision was made following consultation with medical personnel and in accordance with the league’s commitment to the health and wellbeing of players, fans, staff and all those involved in the competition,” the PWHL said in a statement. “A rescheduled date for the game will be announced as soon as medical guidance determines it is appropriate to resume play. An update will be provided to fans within the next day.”

The Associated Press reported that the illness had been limited to Montreal and The Hockey News’ reporting indicated that at least five players on the Victoire had been dealing with some sort of sickness. 

The first-round series between Minnesota and Montreal tied at 2 game apiece, and the winner will advance to face the Ottawa Charge in the Walter Cup final. The Frost have won the PWHL title during the league’s first two years of existence. 

The postponement could create a scheduling headache for the PWHL as it tries to find a date to play Game 5. Place Bell has open dates on Tuesday and Wednesday, but it’s unclear if they would want to schedule a game on the same day the Montreal Canadiens face the Buffalo Sabres at Bell Centre in Game 4 of the second-round NHL playoff series.

The league announced earlier in the day that Games 3 and 4 of the Walter Cup final would take place on May 18 and May 20, though that could now change due to the postponement.