Bruce Cassidy won't be available for Tuesday's game against the Detroit Red Wings.
The Boston Bruins head coach has been placed in the NHL's COVID-19 protocol, the team announced Tuesday morning.
Bruins general manager Don Sweeney will address the media later Tuesday and should provide some clarity on the Bruins' coaching plan in Cassidy's absence.
Joe Sacco is Boston's longest-tenured assistant coach (since 2014), so it's possible he takes over behind the bench at TD Garden. Assistants Kevin Dean and Chris Kelly are potential options, as well.
The Bruins also will be without Brad Marchand on Tuesday after the star forward was suspended three games for slew-footing the Vancouver Canucks' Oliver Ekman-Larsson on Sunday.
After Tuesday's game in Boston, the B's will travel to Nashville to play the Predators on Thursday before returning home to face the Tampa Bay Lightning on Saturday night.