Johnny BoychukBOSTON — Peter Chiarelli has made many difficult decisions during his tenure as the Bruins’ general manager. Trading Johnny Boychuk is just the latest.

“This is a tough trade. We all like Johnny,” Chiarelli said at a press conference before Saturday’s Bruins-Red Wings preseason finale at TD Garden. “This was really hard to do, but there’s an element of business to it, an element of hockey, and we tried to get ahead of it a little bit. He was upset, I was upset. I’m still upset.”

Boychuk was dealt to the New York Islanders on Saturday in exchange for two second-round draft picks (the Philadelphia Flyers’ in 2015 and the Islanders’ in 2016) and a conditional 2015 third-round pick (this selection goes to Boston if the Islanders trade Boychuk to an Eastern Conference team during the 2014-15 season).

“This deal was bordered around a couple things,” Chiarelli said. “One, our cap situation. Two, trying to be proactive on team planning. 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. I wish I could do everything at once. We were involved in some deals for players, and as I said to you back in June or July, this is stuff we have to peck away at. Unfortunately, this is the type of stuff that comes first.

“I feel we got very valuable return. Those are real viable picks that can be used to draft players or acquire players.”

The Bruins entered Saturday a little less than $500,000 under the cap ceiling (per CapGeek), and moving Boychuk’s $3.36 million cap hit gives the team more roster flexibility. Another thing to consider is the abundance of Bruins players eligible for unrestricted or restricted free agency after this season. Reilly Smith (RFA), Torey Krug (RFA), Carl Soderberg (UFA) and Dougie Hamilton (RFA) are among a group of 12 players Boston needs to consider signing between now and July 1, 2015.

“We’ve got a lot of people to sign here, and there’s a list of priorities and part of my job is to prioritize things,” Chiarelli said. “… 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. And I’ve tried to keep the critical mass together, and I’ll continue to provide the right moves for the organization.”

Boychuk was a well-liked player among the fans and his teammates. He arrived in Boston in 2008 and became a second-pairing, shut-down defenseman capable of playing both special teams units and providing a booming shot from the point. This trade doesn’t help the Bruins right now, but it allows them to see which young players are capable of stepping up and filling the void.

“As far as the team, I feel good about the team,” Chiarelli said. “I think there’s still areas where we can tweak, and that’s my job over the course of a shorter period of time — shorter meaning I’d like to see how these guys look in 10, 15, 20 games. We’ve got some young players that are pushing, and we’ll see how that goes. So 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. 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.”

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