WILMINGTON, Mass. — The Boston Bruins’ opening-night roster might still look significantly different from the one you see July 17.

Bruins general manager Don Sweeney said Friday the door remains open for the team to add additional free agents before the 2015-16 regular season begins this October.

“There are still players out there that may fit,” Sweeney said after the final day of Bruins development camp at Ristuccia Arena. “You have conversations with agents about possibilities. I think we’re comfortable with where we are in creating internal competition, but I’m not going to stop sort of asking in areas that we can continue to look at.”

The Bruins already have made several transactions this summer, signing free-agent forward Matt Beleskey and defenseman Matt Irwin and swinging a trade for former Florida Panthers forward Jimmy Hayes. The team also has made a number of deals with eyes on the future, stockpiling draft picks by trading away mainstays Milan Lucic and Dougie Hamilton as well as newly acquired goalie Martin Jones.

Sweeney, who in May replaced ousted GM Peter Chiarelli, said it’s too early to judge whether the moves he’s made thus far will translate to greater on-ice success this season.

“Again, knowing that there was going to be some change, you can talk about planning, but until you’re having conversations to what materializes, you don’t necessarily absolutely know,” he said. “There’s just no absolute in this game. From start to finish and until the red light goes on that particular night — that’s the only absolute we have.

“Were there areas that we needed to change and address and have some flexibility in some things? Yeah, there were. And I’m on record as saying, three very good players left our organization (Lucic, Hamilton and Reilly Smith, who was included in the deal for Hayes). And we’re hopeful that the players that we brought in are going to have an impact.”

One spot most agree the Bruins still need to improve is the on blue line. When asked how comfortable he is with Boston’s current group of defensemen, Sweeney seemed to agree with that assessment.

“Well, you’re always going to want to have the best group you possibly can,” the GM said. “There’s probably an element of the unknown, because we have some guys that are going to push (for roster spots). But we have waiver decisions — there are certain things that impact the decision overall. There are a couple of free agents that we still have conversations with that we felt might improve our club if the financial component works, and we’re not going to stop having those conversations, because they might be the right thing to do. Matt Irwin coming on I think helps provide a lot of depth for our overall grouping.

“… But we have some younger players that at some point in time have to be given an opportunity if you believe in them. And for me, that’s an exciting part of the game. Yes it is. It’s a little bit of the unknown. I’m not going to sit here and blow smoke in any direction that it’s not. It absolutely is. Would a coach like to have four guys that have been in the All-Star Game the previous year? Yeah. If he can pencil that in, I’m sure he’s going to say, ‘Let’s check that box right off.’ But at times, it doesn’t happen that way. We’ve got five players who are returning who have played for your hockey club that had a lot of success, that I think you’ve got a foundation there.”

Thumbnail photo via Bill Sikes/Associated Press