Hnidy/By S. Bradley

BOSTON — Two years ago, Matt Hunwick’s emergency spleen surgery opened a lineup spot for Shane Hnidy.

This season the Bruins signed Hnidy as an insurance policy against a similar situation. Although all signs point to Zdeno Chara playing in tonight’s Game 2 of Boston’s Eastern Conference quarterfinal series with Montreal at TD Garden, the captain’s bout with dehydration once again highlighted the importance of having a player like Hnidy around.

While Hnidy couldn’t possibly be more of a polar opposite in terms of talent and size, he has the experience to at least go in the lineup and not hurt Boston.

Although he played just three regular-season games, Hnidy says he’s ready to fill in when needed.

“That’s why I’m here. You’ve got to have that kind of mindset that every day, regardless of the situation, you’re coming in preparing to play. And when told otherwise, you look after that,” Hnidy said after he was one of a handful of Bruins to partake in an optional morning skate. “But on game days, [I have] kind of my routine, and anyone that’s sitting out here [in the room] we’re trying to get the mindset that you’re going to play and preparing that way.”

Sometimes sitting out can be more taxing on the body than playing because of all the off-ice work the training staff puts idle players through. Hnidy said that hasn’t been an issue.

“I feel good. I think there’s a time and a place you need to rest. And they’ve been great here, the whole staff has made sure that at times when to push us and when to back off a bit,” he said.

The Bruins don’t want to find out what life without Chara would be like. But it’s worth noting that when he filled in for Hunwick against the Habs two years ago, Hnidy scored a key goal in the victory.

At least he might be able to help down the road if one of Boston’s less-important defensemen has a reason to miss a game.