Boston gets forward Brad Marchand (upper-body) back for the Winter Classic after he missed a 3-2 overtime win at the Buffalo Sabres on Saturday, but McAvoy did not practice at Notre Dame on Monday and has been ruled out for Tuesday; his next opportunity to play would be against the Calgary Flames at TD Garden on Thursday.
McAvoy last played in a 5-3 loss at the Carolina Hurricanes on Dec. 23 and missed 20 games earlier this season with a concussion.
The defenseman is one of the players who have missed not just a few games here and there, but significant chunks of the season; Chara missed 19 consecutive games with a knee injury. Bergeron (rib/collarbone) missed 16. Miller missed 13 with a hand injury, returned for four, and missed another 13 with a throat injury. DeBrusk missed nine with a concussion. Defenseman Brandon Carlo missed nine with an upper-body injury.
That left the Bruins with a makeshift lineup at times, at one point playing with three defensemen who had seemed unlikely to see the NHL at all this season, let alone at the same time. On Nov. 17 against the Arizona Coyotes, for instance, the Bruins dressed a defense that included Jakub Zboril, Connor Clifton, Jeremy Lauzon and Steven Kampfer, in addition to Krug and Matt Grzelcyk, and somehow managed a 2-1 win.
Though Boston (21-14-4) has survived, sitting in the first wild card into the Stanley Cup Playoffs from the Eastern Conference, it's heartening the Winter Classic will finally be more about the players on the ice than the ones who aren't.
"For short term, it's good for the fans, good for the event as well to have those big names back in," DeBrusk said. "I think for long term as well for our team, I think having those guys back, myself included, and [Miller], just everyone getting healthy, it's always a good sign. Lots of leadership there."
That doesn't mean that things will be perfect.
Said Cassidy: "The danger [is] in thinking as soon as you get healthy is that everyone is going to be firing on all cylinders right away. I think it takes time. It takes time for [Chara]. It's going to take time for Kevan Miller. They missed time. Even [Bergeron] had a great first game back and I'm sure he'd be the first to tell you he's not probably where his game needs to be at after missing five weeks."
That was evident when the Bruins lost to the struggling New Jersey Devils 5-2 at home on Thursday, despite getting back Chara, Miller and DeBrusk. Everything did not suddenly come together.
Though it continues to be a process to become the team they were constructed to be this season, one that could contend for the Stanley Cup even with a difficult road ahead in the Atlantic Division, the Bruins are more than happy to take a step forward Tuesday.
"I don't think we're where we need to be as a team yet, and I don't think it'll happen as soon as tomorrow just because some guys are healthy," Cassidy said. "I think it takes a while."
They are closer to healthy, closer to themselves.
"I think that it's nice to have the full lineup again," Chara said. "We've been missing that since training camp. Definitely nice to have everybody back and playing. It's just a matter of now playing like we can and doing it the way that we are capable of."