But from general manager Peter Chiarelli and coach Claude Julien on down through the entire roster, the Bruins are confident they can get through this.
Julien and many of the players don't think there will be any issues without having Chara on the ice. Realistically, given his size and strength, along with his ability to shut down the opposition and average 25 minutes per game, there's no way to replace his contributions.
The "everybody has to step up" attitude sounds appropriate in a case like this.
The Bruins' depth on defense has already been tested. Without Chara and fellow blueliner Kevan Miller (who's out indefinitely with a dislocated shoulder), Boston will need its once-inexperienced defensive core to perform a lot better than it has recently in order for the team to be successful.
Dougie Hamilton and Dennis Seidenberg need to be at their best. Adam McQuaid needs to be this season's version of Johnny Boychuk, the player who goes above and beyond when needed most. Matt Bartkowski, who has been a healthy scratch in six of the nine games so far this season, said all he needed was consistent ice time in order to be able to contribute. He's struggled in the few games he's played this season, and if everyone were healthy, he would be watching from press level.
Torey Krug has made strides in his defensive game, and he'll need to remain reliable with more responsibility coming his way.
Chiarelli was typically noncommittal when asked if he would consider looking outside the organization for defensive help via the trade market, saying: "I don't normally comment on that stuff, I know I have on the forward side of it, and I'll leave it at that. You guys can speculate."
Let the speculation begin.
Since it's so early in the season, it's hard to get an accurate feel for the trade market. Pickings are slim, and at this point anything Chiarelli could add would be more about increasing depth than finding a real difference-maker.
One option could be Hal Gill. The 39-year-old veteran remains unsigned. He could add some depth and insurance for Boston in case the organization's prospects prove not to be ready. Gill would be inexpensive, too.
During Friday's practice at TD Garden, with the Bruins preparing to face the Toronto Maple Leafs on Saturday night at Air Canada Centre, Julien had Seidenberg and Hamilton as his top pair, followed by Krug-McQuaid and Bartkowski-Zach Trotman. Joe Morrow was also in the mix.
The Seidenberg-Hamilton pair is obviously very strong. They've played together in the past and feed off each other well. But now with the team's two best defensemen playing together, it doesn't balance out the rest of the defensive unit.
Seidenberg and Krug have played the past couple of games as a pair and have worked well together. Chiarelli admitted he likes that pairing, too. Seidenberg missed the majority of last season when he tore his MCL and ACL in his right knee on Dec. 27 and had surgery on Jan. 7. The rust from his hiatus is showing this season, but he's beginning to come around.
"I don't think he's struggling. I think he's finding his game," Chiarelli said of Seidenberg. "He's another one, we've got some guys that missed some time and are recovering from injuries and he's one of them and he's finding his game. I've actually liked that pair, I thought that pair's been pretty good. But he's slowly finding his game. If you look closely at his game, he's slowly getting his legs, he's slowly getting his timing back, he's slowly getting his passing back and you're seeing more offensive chances from him. He's skating the puck more, so he will get better."
Trotman and Morrow were both recalled Friday. Chiarelli explained the reasoning for calling up two players by noting that other players are dealing with "a couple of little things," but the GM added it's nothing serious.
"The two guys we're bringing up, they're younger, less experienced players that don't have the résumé that the guys that are hurt have. You make do with what you have at this point. They have their assets; they have their good parts of their game. They're both strong skaters and they're strong, so while they are not pure shutdown guys like Miller or Z, they have their things they can bring to the table and they have to excel at. It's not a change of identity. These guys are strong and they can defend, that's what the consistent thing is."
The other big downside to Chara's absence is the power play. Since Chara moved to the front of the opposition's net during the man-advantage at the start of last season, Boston's power play has improved. He led the team with 10 power-play goals during 2013-14. Now, there's that void, too.
The Bruins believe there will be life without Chara. Goaltender Tuukka Rask provided a decent perspective.
"It's sad to see him gone, but then again, he's getting older and he's not going to be here forever, so we have to get used to playing without him at some point. We might as well take the positive out of it and try to have the guys step up and take his role," Rask said.
Julien said it best: "There's no discouragement in that room. There's no issues there at all, to be honest. It's more about it's opportunities for players, and if we become that bad of a team because one player [is out], it's not a real good sign for our hockey club."
The Bruins better hope they can overcome Chara's absence. If they don't, by the time Chara returns, the team may need to pick up too much ground in the standings.