Marchand scored 3:30 into the overtime, lifting Boston to a 2-1 victory over the Columbus Blue Jackets on Saturday night.
''Yeah, I kind of wanted, was hoping to score just to do it before the game,'' Marchand said of copying McGregor's entrance into rings. ''It's not every day you have an icon here in the room. I just wanted to have a little fun with it.''
McGregor spoke to the team before the game and again after.
''He's an incredible guy, very energetic,'' Marchand said. ''He was humble. He was happy to be here. He's expressed that to everyone. It was an honor to meet him. It was great to have him here. It's something we'll remember.''
The win snapped Boston's three-game losing streak that came after it earned at least a point in 19 straight games. Patrice Bergeron had a power-play goal for the Bruins and set up the winner.
Bergeron spun around and fed Marchand in the right circle, where Marchand one-timed a shot as he went to one knee for his 15th OT goal, most in team history. Then the winger did a little shimmy - with his arms moving back and forth - as he skated to toward the bench before he was mobbed by his teammates.
''It goes to that chemistry,'' Bergeron said. ''We know where each other are going to be on the ice mostly at all times.''
''I thought our whole team played well,'' Blue Jackets coach John Tortorella said. ''I'm not going to single anyone out. I thought it was a good team effort.''
In the OT, Marchand had two close chances for Boston after Halak robbed Duchene's bid from the slot.
This matchup was much different than Tuesday, when the Blue Jackets jumped ahead 5-1 in Columbus before holding off the Bruins for a 7-4 victory.
With McGregor in the building and firing up the crowd before making the ceremonial puck drop, the Bruins and Blue Jackets came out hitting and going end-to-end early before settling into a tight checking game.
Bergeron gave Boston a 1-0 lead with his goal 5:51 into the game, firing a backhander over Korpisalo for his 800th career point.
The Blue Jackets tied it when Duchene broke down the right wing, shifted around defenseman John Moore and lifted a shot over Halak's shoulder inside the near post at 16:52 of the first period.
Duchene said the TD Garden ice wasn't good, with the game started just a few hours after the Boston Celtics beat the Atlanta Hawks on Saturday.
''It was awful ice,'' he said. ''It was probably the worst ice I've played on this league. I don't know what was going on with it. That's probably why it was a 1-1 game (at that time). Pucks were rolling on guys.''
Boston had a handful of good chances in a scoreless second. The best came when Marchand had the puck all alone just outside the crease midway into the period, paused and waited for Korpisalo to drop before shooting it over the net.
NOTES: Columbus' top goaltender Sergei Bobrovsky not only had the night off, he wasn't in uniform and watched from the press box. ... Linesman Brian Murphy worked his 2,000 game and was honored with a pregame ceremony, receiving team-signed jerseys from both clubs. ... Bruins F Jake DeBrusk was back after missing the previous five games with a lower-body injury. ... Boston TV personality Jayme Parker did the PA as part of NHL and NHLPA's Hockey is for Everyone initiative. ... The clubs meet again April 2 in Columbus.
IRISH HERITAGE NIGHT
With pre-St. Patrick's Day excitement filling bars and restaurants outside TD Garden following the Celtics' victory and about two hours before faceoff, the Bruins added some things to the festive night.
They also wore green jerseys during their pregame warmup, brought in members of the Boston police Gaelic Column of Pipes and Drums to play at turnstiles and gave out green hats to the first 5,000 fans.
McGregor got a big cheer when he was interviewed on the Jumbotron and there was a buzz every time he was seen in different parts of the building.
Blue Jackets: At Calgary on Tuesday, their second of a four-game road trip.
Bruins: Open a four-game trip at the New York Islanders on Tuesday.
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