Chiarelli hates to get rid of 'his guys.'

When you go to a Michael Bay movie, you’re expecting explosions and jaw-dropping special effects with mind-numbing dialogue. When you watch David Ortiz hit, you’re ready for a swing for the fences, not a bunt down the line.

And when you look for Bruins roster moves, you expect Peter Chiarelli to do whatever it takes to keep his core together as long as possible.

Chiarelli hates to get rid of ‘his guys.’ Think about how long it took him to come to a decision to let Shawn Thornton go to free agency after last season; a relatively easy choice — he's a 37-year-old brawler with tread on the tires in a league moving away from his skill set — took about a month because of Chiarelli’s loyalty to his group.

There are still 13 players on the Bruins’ roster that raised the Stanley Cup in Vancouver; that was 40 months ago, a stretch that takes a tidal wave to most rosters. The general manager has kept the band together as much as he can.

All of which makes Saturday’s trade of Johnny Boychuk to the Islanders for draft picks so puzzling and surprising, that Chiarelli would betray one of his guys when he could have gone on one more tour with Boychuk.

“I’d love to keep this team together player to player as long as I could if I felt it was prudent on the hockey front and the financial front,” Chiarelli said at his press conference. “And I’ve tried to keep the critical mass together and I’ll continue to provide the right moves for the organization. There’s a lot of factors involved. We could have kept him and if we keep him, we’re not trading him at the deadline. We keep him, we’re using him [all season], so that played into the fact. You can see what you could have gotten at the deadline, but I don’t weigh that as one of the factors here.”

It’s just the second trade since the Cup that Chiarelli has made that moved one of the championship heroes. The other was the 2013 deal that sent Tyler Seguin and Rich Peverley, a salary cap casualty, to Dallas. That was a trade spurred by Chiarelli losing faith in a player he once liked and making what was, at least for the most part, an on-ice deal.

This is nothing of the sort. Chiarelli loves Boychuk, and losing a top-four defenseman in or near the prime of his career makes the Bruins a worse team. Chiarelli conceded as much in his Saturday afternoon press conference.

“This doesn’t make us better now, obviously,” he admitted.

But Chiarelli hinted that perhaps it’s gotten time to not be so loyal to the Vancouver heroes.

“It’s easy to say, ‘Let’s keep keeping the team together and it will subsequently be as we won four or five years ago. It will be the same team and we’ll win.’ Now, it doesn’t happen that way,” Chiarelli said. “Dynamics change, people change, the way they approach things change. And I’m not trying to keep refreshing. It’s just that we want to get better and sometimes you can’t do it in one step. That’s how I see this.”

The fact is the Bruins could have kept Boychuk. This was a trade urged by cap concerns, not made mandatory by cap demands. The Bruins knew they weren’t keeping Boychuk long-term, but they could have kept the looming unrestricted free agent for one more loop through the league before he cashes and taken a run at another Cup with the best squad possible.

Trading Adam McQuaid instead would have left them with around $1.5 million in space; a Matt Bartkowski deal leaves about $1.2 million in spare change. With Boychuk out of the picture, it's $3 million, give or take a couple hundred thousand dollars depending on how the roster shakes out.

So if Chiarelli can spin those extra picks into a top-four defenseman later this season — the Canucks' Alex Edler would make sense, especially with old friend Jim Benning pulling the strings in Vancouver — then perhaps this deal will be evaluated differently down the road.

“I look at this a little bit globally like this may be one in a series of two or three steps throughout the course of the year,” Chiarelli said. “I wish I could do everything at once. We were involved in some deals for players and as I said … back in June or July, this is stuff that we have to peck away at. Unfortunately this is the type of stuff that comes first.”

But deals like that are no guarantee to occur. The trade market was bare-bones last winter, and as long as teams are in contention, they won't be lining up to give up talented blue-liners to Chiarelli. There are no guarantees attractive players will be on the market.

And the Bruins have had difficulty integrating defensemen into their lineup in the middle of the season. In Claude Julien’s first seven seasons, the only defenseman who was acquired mid-stream and played to expectations was Dennis Seidenberg in 2010. Julien's position-based system requires repetition and practice time to learn, a luxury teams rarely have in the busy second half of the season. Andrej Meszaros was never comfortable after 10 weeks in Boston last season.

Yet the Bruins now have the space to make that move, or at least some move, something they wouldn’t have had if it was trading Bartkowski or McQuaid for pennies on the dollar.

The Bruins are left with either Bartkowski or McQuaid presumably stepping into a top-four role. Dennis Seidenberg’s versatility to play both left and right sides allows for multiple options, yet none are as appealing as the heavy, steady Boychuk was.

That’s a scary thought in Zdeno Chara’s age-37 season. The Chara Window is a very real thing, with Chara, Patrice Bergeron and Tuukka Rask all still in the sweet spots of their career, as well as secondary players David Krejci, Milan Lucic, Brad Marchand, Dennis Seidenberg and Dougie Hamilton. The Bruins can still make a run in a weak Eastern Conference.

It’s just they aren’t as powerful right now as they could’ve been, and won’t be until Chiarelli takes that next step. And that was their general manager’s choice.

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