BOSTON -- It took a little longer than they had hoped, but the Boston Bruins defeated the Toronto Maple Leafs in seven games in the Eastern Conference First Round.
After taking a 3-1 series lead, the Bruins lost the next two games and let the Maple Leafs tie the series. But after three comebacks in Game 7, Boston won a Stanley Cup Playoff series for the first time since 2014. The Bruins will face the Tampa Bay Lightning in the second round, beginning with Game 1 at Amalie Arena on Saturday (3 p.m. ET; NBC, SN, TVAS).
Here are five reasons the Bruins advanced to the second round:
[RELATED: Complete Lightning vs. Bruins series coverage]
1. No panic in Game 7
The Bruins trailed by one goal three times in the deciding game, including 4-3 heading to the third period. They responded with four goals in the third and a 7-4 win. Boston's experience in past Game 7s probably helped, but the Bruins won six times in 28 games when trailing after two periods in the regular season (6-17-5) and were 21-18-6 when allowing the first goal.
"We knew that we have the resiliency in the room to continue to come back, we've done it all year, so we just try to draw on that," forward Brad Marchand said. "It doesn't always go your way, but luckily tonight it did."
Video: Bruins outlast Maple Leafs in seven games to advance
2. Big game from big line
The Bruins' top line of Patrice Bergeron centering Marchand and David Pastrnak combined for 30 points (nine goals, 21 assists) against the Maple Leafs. Pastrnak had 13 points (five goals, eight assists), including three goals and three assists in a 7-3 Game 2 win. Marchand had nine points (three goals, six assists), and Bergeron had eight points (one goal, seven assists) despite missing Game 4 with an upper-body injury. Pastrnak, Marchand and Bergeron scored in Game 7.
"Toronto did a good job with them. They got frustrated a few times, but they stuck with the program," Boston coach Bruce Cassidy said. "Even the games they've been quiet in terms of stats on the sheet, they've been generating [chances]."
3. DeBrusk's emergence
Rookie forward Jake DeBrusk didn't wilt under the pressure of his first Stanley Cup Playoff series. He had seven points (five goals, two assists), including two goals in Game 7.
"There's something inside of him that not many guys have," Bruins defenseman Torey Krug said. "He hounds the puck. He stays on it ... when he wants it he's going to get it, so he's a great player for us."
Video: Bruins, Lightning prepare for Second Round showdown
4. Rask comes through
Goaltender Tuukka Rask did not have a game he'll put on his highlight reel in Game 7, allowing four goals on 24 shots. He finished the series with an .899 save percentage.
But when the Bruins needed him to hold the Maple Leafs in the third period of Game 7, he stopped all eight shots he faced.
"[Toronto goaltender Frederik Andersen] got hot there in the second period, so we stuck with it, but I don't think there was a doubt that if we got ourselves back tied or in the lead that Tuukka would be fine down the stretch," Cassidy said. "The guys have confidence in our goaltending; they have all year. Both goalies, obviously big moments. There's a lot of pressure on them, and we saw it at both ends. At the end of the day, [Rask] found his game, and like I said, we picked each other up and off we went."
5. Maple Leafs' stars silenced
Facing the defense pair of Zdeno Chara and Charlie McAvoy for most of the series, Toronto center Auston Matthews, who had 63 points (34 goals, 29 assists) in 62 regular-season games, was limited to two points (one goal, one assist) in the seven-game series.
Toronto center William Nylander, who was shuffled with different linemates, had four points (one goal, three assists) in the series after he had 61 points (20 goals, 41 assists) in 82 regular-season games.
The Bruins' best offensive players thrived in this series and their best defenders made sure the Maple Leafs' most dangerous players were kept at bay.
Video: The guys discuss the Bruins' Game 7 win over Toronto
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