The Boston Bruins traded defenceman Brad Stuart and forward Wayne Primeau to the Flames on Saturday for defenceman Andrew Ference and forward Chuck Kobasew.
The Flames expect both Stuart and Primeau to be in the lineup on Sunday when Calgary ends a three-game road trip in Detroit.
It's the second big deal made by Flames GM Darryl Sutter in the past two weeks. Calgary acquired centre Craig Conroy from Los Angeles on Jan. 29.
Stuart, a key player in last season's deal that sent former Bruins captain Joe Thornton to San Jose, had been mentioned in recent trade talk because of his upcoming free-agent status.
Boston's inability to work out a new contract with Stuart forced the deal, completed just over an hour after the Bruins beat the New York Islanders 4-3 in a shootout.
"It became evident that when I wasn't having success signing Brad that I was going to have to trade Brad," general manager Peter Chiarelli said.
Stuart, 27, was acquired with Primeau and Marco Sturm on Nov. 30, 2005, for Thornton - who went on to win NHL MVP honours with the Sharks last season.
Boston missed the playoffs and is in danger of doing so again this year. They're last in the Northeast Division with 54 points.
"When any team doesn't win hockey games something has to change," Boston coach Dave Lewis said.
Stuart has seven goals and 10 assists in 47 games this season, but has struggled defensively on the underachieving Bruins with a minus-23 rating.
His best season was with the San Jose Sharks in 2003-04, when he had 36 points and a plus-9 rating.
The six-foot-two, 213-pound native of Rocky Mountain House, Alta., was San Jose's first-round pick, third overall, in the 1998 NHL entry draft.
He has 201 points and 285 penalty minutes with a minus-2 rating over 479 career games with San Jose and Boston.
Stuart joins a talent-rich Calgary blue-line already boasting the likes of Robyn Regehr, Dion Phaneuf and Roman Hamrlik.
Primeau is also an unrestricted free agent at the end of the season. He had seven goals, eight assists and 73 penalty minutes in 50 games for the Bruins this campaign.
Primeau was Buffalo's first round pick, 17th overall, in 1994. The six-foot-four, 231-pound Toronto native never displayed the scoring touch in the NHL that he showed in a promising Ontario Hockey League career with Owen Sound and Oshawa. His best season was also 2003-04, when he had 29 points and 90 penalty minutes in 72 games with the Sharks.
Primeau has 165 points and 676 penalty minutes in 620 career games with Buffalo, Tampa Bay, Pittsburgh, San Jose and Boston.
Ference, 27, played in 53 games this season for Calgary. He is signed for three more seasons.
"Part of what we have to do is preserve the assets of players that are unrestricted," Chiarelli said. "Chuck is 24 and Andrew is 27. They add some youth and energy, which we want to add to this team."
Kobasew, who played on Boston College's 2001 NCAA championship team before going pro, appeared in 40 games with Calgary - notching four goals and 13 assists.
Ference played in Buffalo on Saturday night. Kobasew has been sidelined with an elbow injury since late January.
"I'm really looking forward to it," Kobasew said in a statement released by the Bruins. "It's disappointing to leave Calgary, but I did play two years of my career in Boston; one at Boston College and one at Lowell in the AHL."
Ference was surprised to be sent away by the Flames.
"It's always a bit of a shock when you get traded," he said. "But obviously when you're traded to a storied franchise it's definitely a little easier to take."
Chiarelli hopes this trade shows he is trying to build a winner now while also looking toward the future.
"I would like to think it says that we're getting two high-character players and we have an influx of youth and energy," he said. "I don't want to send a message that we're throwing in the towel. These are players that are on a division-leading team with experience. They're good players."