BOSTON – Brad Marchand had a brilliant regular season with 100 points and will get his share of Hart Trophy votes when the NHL awards come down in a couple of weeks.

But the B’s left winger is going to have a long time this offseason to think about what went wrong for him and for his linemates in Boston’s 4-1 loss in Game 7 of the Stanley Cup Final at TD Garden on Wednesday night.

Marchand finished with just two goals and a minus-2 rating in the best-of-seven series, and had zero points in a decisive Game 7 loss.

But it was Marchand's defensive miscue at the end of the first period that essentially doomed the Black and Gold in Game 7. Marchand signaled for a line change with fewer than 15 seconds remaining in the second, and then watched as both Jaden Schwartz and Alex Pietrangelo skated by him into the B’s offensive zone while he retreated to the bench.

Marchand’s absence allowed Schwartz and Pietrangelo easy entrance to the Bruins' offensive zone, where Pietrangelo snapped a backhanded wrist shot past Tuukka Rask. The back-breaking tally gave the Blues a two-goal lead with eight seconds remaining in the first period and effectively knocked the wind out of the Black and Gold in a death blow they would never recover from.

“I don’t know, they chipped it in. I thought that [Jaden Schwartz] was by himself, so I went for a change, and a couple more guys jumped up on the play,” said a teary-eyed Marchand, who appeared to have the entire play develop in front of him as he decided to make the change at the Bruins' bench. “I didn’t see the replay, but yeah.”

Marchand's decision to make a change with roughly 10 seconds to go in the first period ended up being disastrous for the Bruins, and head coach Bruce Cassidy didn't mince any words about it, describing it as probably the turning point in Game 7.

“The second [goal allowed] we just didn’t manage the puck. We kind of missed an assignment and they made a play, a nice play by Pietrangelo but you’re probably [talking] a different game if it’s 1-0 coming out of the first, I do believe that,” said Cassidy. “I’m not saying that we would have won or we would have lost. I’m not a mind reader. But I do believe that it gave them a lot of juice for a period that they, you know if they looked at it objectively, probably felt or should have felt that they got outplayed but they’re up 2-0 on the scoreboard. That’s all that matters.”

Marchand has done great things for the Bruins throughout his career and he’s one of the veteran B’s players who helped get the Black and Gold all the way to Game 7 of the Stanley Cup Final. He’s also one of the experienced veteran guys for the Bruins who they rely on to play solidly in those big game moments in the postseason.

But that decision to get off the ice right before the second goal for St. Louis is one that’s likely (and appropriately) going to stick with the Nose Face Killah for a long time this offseason and beyond.

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