The Bruins, who advanced to the Stanley Cup Final with a 4-0 win, said the 42-year-old defenseman is day to day with an undisclosed injury.
"We found out this morning he wasn't going to be able to go," Boston coach Bruce Cassidy said. "He is dealing with an injury. This time off will help him, and I believe he'll be ready to go in Game 1 (against the winner of the Western Conference Final between the San Jose Sharks and St. Louis Blues), whenever that is.
"We don't think it's serious, but I have said that before about some of our guys and found out later (it was). ... I believe he will be ready to go next round."
John Moore replaced Chara in the lineup and started on the left side of the third defense pair with Connor Clifton. He had one blocked shot in 11:48. Matt Grzelcyk, who is usually the left-handed defenseman on Boston's third pair, moved up to play with Charlie McAvoy on the top pair and had two blocked shots in 16:10.
Torey Krug and Brandon Carlo remained the second pair.
"Without [Zdeno] it was a little more of a challenge, but you've got to give Torey and [Grzelcyk] some credit for handling some big bodies in the tough areas," Cassidy said.
Chara played in Boston's first 16 games of the Stanley Cup Playoffs, including 22:06 in a 2-1 win in Game 3 on Tuesday. It was the first playoff game he missed since sitting Game 2 of the Eastern Conference Quarterfinals against the Montreal Canadiens on April 16, 2011, ending his streak of 98 consecutive games.
Chara didn't participate in Boston's full-team practice Wednesday, but he skated and was seen stretching and working out around the Bruins dressing room Thursday morning.
"[We had a] little inclination this morning with the morning skate, but you never know with a guy like that," Boston forward David Backes said. "Whatever is wrong with him, he may just say '... I'll take it and move on.' Hopefully this little break gets him back to health and he'll be ready for Game 1 and ready to rock."
Chara has three points (one goal, two assists) and is plus-11 in the playoffs. He has 65 points (17 goals, 48 assists) in 175 NHL playoff games.
