BOSTON -- During his seven seasons playing for the Boston Bruins, Shawn Thornton owned the locker room.

His real estate was one of two corner stalls in the room, with captain Zdeno Chara setting up shop in the other. Now, first-year Bruin and 15-year veteran forward Simon Gagne has Thornton’s former seat in the room, but no one has replaced his personality or voice.

With the Bruins dealing with salary-cap constraints, and with general manager Peter Chiarelli believing the game is trending away from fighting, the organization opted not to re-sign Thornton last summer. So the 37-year-old, two-time Stanley Cup-winning veteran took his character and abilities to South Florida and signed with the Panthers for two years and $2.4 million.

On Tuesday, Thornton and the Panthers will face the Bruins at 7 p.m. at TD Garden. It will be Thornton’s first time back since leaving his No. 22 Bruins sweater behind.

Shawn Thornton, who returns to Boston on Tuesday, provided a personality and leadership that the Bruins can't replace. Christian Petersen/Getty Images

“It’s a little quieter,” Bruins assistant captain Chris Kelly said with a laugh. “Shawn was a big personality, on the ice and off the ice. He did a lot for the team and the community. Not just one guy is going to be able to fill his shoes. It takes a group effort to try to fill that void of such a large personality, a guy that’s won two Stanley Cups and has been around for a long time. There are certain days that are a little more quiet than others, and I’m sure that has a lot to do with Shawn.”

There’s definitely a different atmosphere around the Bruins this season without Thornton.

“Shawn’s a little more vocal than most guys in the locker room, so it’s definitely a little more quiet,” Daniel Paille said. “But guys have been stepping up, especially the last couple of weeks, talking a little bit more and kind of breaking out of their shell.”

Sure, there are other leaders in the room with the likes of Chara, Kelly and Patrice Bergeron, but Thornton had his own style. He was never afraid to speak his mind and was always honest. He also knew how to motivate his teammates.

Probably the best example of his motivational skills came prior to Game 7 of the Eastern Conference finals against the Tampa Bay Lightning at TD Garden in 2011.

Thornton and then-Bruins teammate Shane Hnidy both were healthy scratches for that game, so while their teammates enjoyed their game-day naps, the two veterans spent the afternoon transforming the Bruins’ locker room.

With only one win keeping the Bruins from advancing to the Stanley Cup finals, Thornton ordered five black-and-white, autographed pictures of former Bruins teams celebrating their championship victories in the locker room. He strategically placed the photos in the room, so when his teammates arrived they were greeted with images of the celebrations.

The idea worked.

As Thornton watched from press level, the Bruins defeated the Lightning 1-0 in a dramatic game to advance to the Stanley Cup finals. Boston eventually won the Cup with a seven-game series win over the Vancouver Canucks.

Thornton loves everything about Boston. He loves its restaurants. He loves its sports teams and all the fans. His permanent home is in Charlestown and whenever his career is over, he’ll likely transition to the media side of the game for an outlet in Boston.

On the ice this season, there have been only five fighting majors for the Bruins. Bobby Robins, currently with the Providence Bruins of the AHL, had two fights earlier this season, and Adam McQuaid, Kevan Miller and Milan Lucic have dropped the gloves once each.

Thornton has dropped the gloves only once this season for the Panthers.

“On the ice, he has that impact, that intimidation factor game in and game out,” Paille said. “On the bench, he’s definitely vocal and trying to pump up guys. When he’s on the ice, you know he’s giving everything he has skating, and hitting, and he’ll do anything he can to get a win for us. We all know what he’s capable of and we definitely miss that aspect of his game. We’re finding that identity now to change a little bit more.”

Thornton, Paille and Gregory Campbell made up the team’s energy line, or “Merlot Line,” named for the color of their practice sweaters. The trio was one of the better fourth lines in the league and allowed Bruins coach Claude Julien to roll four lines most nights.

Thornton did more than just drop the gloves during his time with the Bruins. There’s a void in the room and the team’s dynamic on the ice has changed too.

“Yeah, it’s been different,” Bergeron said. “He’s definitely one of the guys that we’ve been through a lot together and it’s definitely different to see him gone and not with us. Hopefully things are going well in Florida for him.”