Chara, a 42-year-old defenseman, has an undisclosed injury. John Moore replaced him in the lineup.
After the final buzzer, Chara was in uniform and came onto the ice to celebrate with his teammates.
Chara spoke to reporters on the Wednesday off day and was seen in the arena Thursday morning. He had been set to play in his 176th career playoff game, which would have tied him with current San Jose Sharks player Joe Thornton and Mike Modano for 40th all-time in playoff games.
Chara typically plays on the Bruins’ top pairing alongside Charlie McAvoy. In 16 playoff games this spring, Chara has averaged 22:32 of ice time per game, with one goal and two assists.