PITTSBURGH -- Kris Letang said Monday he did not become a defenseman as a teenager just so he'd get to be on the ice more often during games.

That's just an added benefit.

Letang is seemingly everywhere in every situation for the Pittsburgh Penguins, who open their Eastern Conference Semifinal series against the Ottawa Senators on Tuesday (7:30 p.m. ET, NBCSN, CBC, RDS).

One of three finalists for the Norris Trophy as the top defenseman in the NHL, Letang's value to the Penguins was on display in a six-game quarterfinal series victory against the New York Islanders.

Who would have thought there'd be the opportunity to write this story?

With the Boston Bruins down 4-1 and nearly half the third period salted away in Game 7 of the Eastern Conference Quarterfinals against the Toronto Maple Leafs on Monday night, it looked like the Maple Leafs would be the team in this space.

But the Bruins authored a miracle comeback win worthy of joining many of their greatest victories to eliminate the Maple Leafs 5-4 in overtime and set up a second-round showdown against the New York Rangers in the Stanley Cup Playoffs.

It's almost impossible to put into words how the Bruins got past Toronto. Still, here are five reasons the Bruins advanced to the second round for the first time since 2011:

WASHINGTON -- No offense to New York Rangers forward Arron Asham, but it doesn't bode well for the Washington Capitals when a fourth-liner like him outscores Alex Ovechkin in a seven-game series.

Asham did just that in the Eastern Conference Quarterfinals. Not surprisingly, Ovechkin and the Washington Capitals are done.

Ovechkin was held off the scoresheet for the final five games of the series and was limited to one shot on goal in a 5-0 Game 7 drubbing on Monday at Verizon Center. He had a goal in Game 1 and an assist on Mike Green's overtime winner in Game 2, but nada, zippo, nothing after that even though he got 30 shots on goal in the series.

Despite seeing a lot of both Ryan McDonagh and Dan Girardi, Ovechkin gave all the credit for his lack of success to Rangers goalie Henrik Lundqvist, who went the final 120 minutes of the series without allowing a goal.

Henrik Lundqvist

Goalie - NYR

RECORD: 4-3-2
GAA: 1.65 | SVP: 0.947

His ability to shrug off Mike Ribeiro's goal and produce back-to-back outstanding performances in Games 6 and 7 proved to be a big part of why the New York Rangers were able to upset the third-seeded Washington Capitals and advance to a second-round date with the Boston Bruins.

"The last couple of years, I've started to focus more and more on my own game and not so much about the team game," Lundqvist said after a 5-0 win in Game 7 Monday night. "I can't really control what we're doing out there. That's been helping me the last few years. Obviously in big games, if I can break it down to just what I need to do it is going to help. You're definitely nervous and you're feeling the pressure. As long as I'm focused on what I have to do, it is going to help me, but the way we've playing, especially the last two or three games, as a goalie it is a great feeling. You feel the confidence from them, and hopefully they feel my confidence as well."

BOSTON -- So how exactly did the Boston Bruins rally from a 4-1 deficit to fashion a dramatic 5-4 overtime win on hockey's biggest stage -- Game 7 of a Stanley Cup Playoffs series.

It depends on who you ask.

Toronto coach Randy Carlyle thought his team's gas tank hit empty after Nazem Kadri scored 5:29 into the third period for a 4-1 lead. He says his players didn't have the energy reserves to successfully navigate the 14-plus minutes of the contest.

So instead of riding out the storm and pocketing a victory, the Maple Leafs allowed three goals in the final 10:42 of regulation to force overtime, which ended when Patrice Bergeron scored his second goal of the game at 6:05.

"Just trying to chew the clock, get the game down," Carlyle said of his team's mindset after delivering what seemed like the knockout punch to the Bruins. "You know they scored the one goal that gave them some life and we got it to a minute and a half and you knew the goaltender was going to be coming and we give up a goal that we thought, we still had a chance with the goalie out and they found a way to push one over the line. It just seemed like we ran out of gas."

BOSTON – The lasting image of Patrice Bergeron's first-round series in the 2012 Stanley Cup Playoffs was his inability to get enough mustard on his shot in overtime to beat Washington Capitals goaltender Braden Holtby in Game 7.

Patrice Bergeron

Center - BOS

GOALS: 3 | ASST: 1 | PTS: 4
SOG: 32 | +/-: 2

Bergeron, who was unable to take faceoffs for much of that series, revealed days after the Boston Bruins' Game 7 loss that he had been struggling with an oblique injury that would take time in the offseason to heal.

A mostly healthy Bergeron made sure Monday night that regardless of how the Bruins' run in the 2013 postseason ends, he'll always be remembered for something 180 degrees different from what transpired in 2012.

Bergeron capped one of the greatest comebacks in NHL postseason history with the game-tying goal with 50.2 seconds remaining in regulation, and then he won the game 5-4 with a goal 6:05 into overtime against the Toronto Maple Leafs at TD Garden.

The Toronto Maple Leafs were so close to winning their first Stanley Cup Playoff series since 2004 that they could taste it. Toronto led the Boston Bruins 4-1 midway through the third period and 4-2 with less than 90 seconds remaining in regulation in Game 7 of their Eastern Conference Quarterfinal series -- only to see Boston score a pair of sixth-attacker goals to force overtime. Patrice Bergeron's goal 6:05 into overtime gave the Bruins a stunning 5-4 victory, making the Maple Leafs the first team in playoff history to lose a Game 7 after leading by three goals in the third period.

It was an agonizing finish to what had been the best season in Toronto in nearly a decade. Here are five reasons the Maple Leafs are going home for the summer:

The Boston Bruins' reward for perhaps the greatest comeback in the history of the Stanley Cup Playoffs is their first postseason series against the New York Rangers in 40 years.

Both teams advanced by winning Game 7 on Monday night, but their paths to victory couldn't have been more dissimilar. The Bruins became the first team to win a Game 7 after trailing by three goals in the third period when the rallied to beat the Toronto Maple Leafs 5-4 in overtime at TD Garden. Patrice Bergeron tied the game with 50.1 seconds remaining in regulation, then scored the series-winner 6:05 into OT.

There were no such worries for the Rangers, who won a Game 7 on the road for the first time in franchise history by blowing out the Washington Capitals 5-0 at Verizon Center. Henrik Lundqvist stopped 35 shots for his second shutout in as many days.

The Original Six clubs had one of the NHL's great rivalries in the early 1970s, when they met in the postseason three times in a four-year span. Boston won a bitter six-game quarterfinal series in 1970 on the way to the Stanley Cup and beat the Rangers in six games two years later to win the Cup again. The Rangers got a measure of revenge the following year when they routed the Bruins in five games in the Quarterfinals.

It's odd to hear the Detroit Red Wings sound like underdogs, but that's what happens to seventh-seeded teams in the Stanley Cup Playoffs.

Rather than the usual role of favorites, the victorious Red Wings – the Western Conference's seventh seed – flew home after eliminating the Anaheim Ducks on Sunday night knowing they'd be right back to underdogs just as quickly as their plane's tires touched ground in Detroit.

Just that quickly, the page was turned on their upset of the second-seeded Ducks in Game 7 of an exciting Western Conference Quarterfinals series. Just that quickly, they shifted to the next challenge: facing the top-seeded Chicago Blackhawks in the conference semifinals, a team they didn't beat in four games this year.