That doesn't mean he can't still enjoy sticking it to the other organizations that left him spending the bulk of his first 10 professional seasons down in the American Hockey League. That includes Tuesday's opponent.
The Chicago Blackhawks make their lone visit to the Garden, and Thornton will enjoy the chance to catch up with some familiar faces from the five years he spent in Chicago's organization from 2001-06.
"It's always a little bit extra when you get to play against a team you used to be a part of," Thornton said. "I know a lot of those guys. I played in the minors with a lot of those guys. I still talk to their assistant coach [Mike Haviland] who was my head coach in Norfolk [Chicago's AHL affiliate at the time]. So there's a little bit more. I always get excited to play those guys."
After being drafted by the Maple Leafs in the seventh round of the 1997 draft, Thornton spent his first four seasons with Toronto's AHL affiliate in St. John's without ever getting called up to the big club. So he appreciated getting his first NHL time with the Blackhawks, though it amounted to just a total of 31 games in Chicago over his five seasons in that system.
"I got my first break with them," Thornton said. "I spent a lot of time going up and down, a lot of cups of coffee, up and down with them. So I always like to play against teams I used to play for."
Thornton got the last laugh when he signed with Anaheim as a free agent in 2006 and won a Stanley Cup with the Ducks the following spring. That summer, he signed with Boston and hasn't spent a day in the AHL since, posting career-best 9-9-18 totals so far this season to go along with his usual team-leading 122 penalty minutes and 14 fighting majors.
The Blackhawks have done all right since Thornton left, too, ending their 49-year title drought by winning the Cup this past spring. They've struggled a bit this season after salary-cap issues forced them to jettison much of their championship squad over the summer, but a strong nucleus remains. Thornton knows the Blackhawks will still be a tough challenge for the Bruins.
"You can't take it away from them," Thornton said. "Obviously they have guys who know how to win. It's not an easy thing to do, so it's still a part of their team, that's for sure."
Facing Chicago could also be a good measuring stick for the Bruins as they get ready for this year's playoffs after clinching a spot with Sunday's win in Philadelphia.
"I'm more worried about us in here, but they're definitely still a good team," Thornton said. "Any time you play a good team, you're testing yourselves a bit I suppose."
Other than his one season in Anaheim, Thornton has spent his entire 14-year pro career in Original Six organizations with Toronto, Chicago and Boston. The Bruins are in the midst of a run of four straight home games against Original Six rivals, having hosted Montreal and the New York Rangers last week with Chicago and Toronto coming to town this week. Those are games that Thornton always looks forward to, even if he sometimes has to shut off his phone the day before to avoid the extra ticket requests.
"I like when you get to play an Original Six team," Thornton said. "I'm sure I'll be getting a lot of calls for tickets. People like to see those games when those teams come to town. It'll be fun."