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There was a point on Monday when it appeared the second-round playoff picture was coming into focus, but like many things in the NHL postseason, it was all about to change in a hurry.

Monday featured a pair of Game 7s in the East as the Boston Bruins hosted the Toronto Maple Leafs and the Washington Capitals welcomed the New York Rangers. Heading into the decisive matchups, it was known the winners of each contest would meet each other in the second round.

Toronto led 2-1 after two periods and scored twice early in the third period to grab a 4-1 cushion with less than six minutes gone in the final stanza. Around the same time, the Rangers scored twice early in the second period to grab a 3-0 lead, making the possibility of a New York-Toronto battle seem highly likely.

Then, as hockey writers across North America prepared to write some version of a Phil Kessel redemption story, the Bruins' offense rose from its slumber. When the dust settled, Boston had won a 5-4 overtime decision and was moving on to the second round, while Kessel and the Maple Leafs were left to wonder what went so wrong.

There was no such drama in the final Rangers-Caps contest, however, as New York goaltender Henrik Lundqvist posted his second straight shutout to lead the Blueshirts to an easy 5-0 win.

With Round 1 coming to a wild finish on Monday, the NHL is plowing right into the conference semifinals on Tuesday. Here's a quick look at the those second- round matchups, which includes two battles between Original Six rivals.

EASTERN CONFERENCE

(1) Pittsburgh vs. (7) Ottawa

Pittsburgh's roster may read like an All-Star lineup, but that's unlikely to scare off a club as resilient as the Senators.

Although the Penguins boast the likes of Sidney Crosby, Evgeni Malkin, Jarome Iginla, Kris Letang and James Neal, the high-scoring group still struggled to keep the puck out of its own net in a six-game series win over the New York Islanders in Round 1. A switch in net from Marc-Andre Fleury to Tomas Vokoun stabilized things, but the Pens could be in trouble against the disciplined Sens, one of the more dangerous seventh seeds you'll ever see.

This series pits the league's best offense against the second-ranked defense, as Pittsburgh led the NHL with 3.38 goals per game in 2013 and Ottawa was second in defense with an average of 2.08 goals surrendered each tilt. The Penguins also won all three meetings with Ottawa during the regular season, but Ottawa was able to slow down the Pittsburgh's power play, as it scored once on 15 chances with the man advantage in the season series.

Although Ottawa finished 27th in team offense during the regular season, a healthy Senators team averaged four goals per game in the opening round against second-seeded Montreal, which wilted in five games against the Sens. Only Pittsburgh had a better scoring average in Round 1, as it posted 4.17 goals per game against the Isles.

The possible return of top centerman Jason Spezza also could help Ottawa become even more dangerous on offense. Spezza, who has returned to practice, hasn't played since the fifth game of the season and is coming off back surgery, but he is a proven playoff performer.

Since winning it all in 2009, Pittsburgh hasn't lived up to its perennial Stanley Cup favorite status. The Pens have shown a tendency to break down defensively in the playoffs in recent years and their play against the Islanders did nothing to change that perception. If Pittsburgh fails to show discipline in this series, expect Paul MacLean's opportunistic Sens to make life miserable for the favorites.

After surviving a regular season filled with injuries, the Senators are riding a wave of momentum into the second round. It won't be a quick series, but Ottawa is primed to pull off the upset against the Penguins.

Senators in seven

(4) Boston vs. (6) New York Rangers

The Bruins are riding high after their thrilling Game 7 win over Toronto, but, unfortunately, so is Lundqvist.

New York's perennial MVP, Lundqvist closed out the Capitals by posting consecutive shutouts in Games 6 and 7. All told, the reigning Vezina Trophy winner stopped 214-of-226 shots in the seven games for a .947 save percentage and a 1.65 goals against average.

The Rangers play a steady shot-blocking style in front of Lundqvist, a strategy that could've helped Toronto stem the tide late in Game 7 against the Bruins. New York has its issues on offense, however, and is still waiting for offseason acquisition Rick Nash to get untracked in the postseason.

Boston is a similar team to the Rangers, one which places defense first for the most part. Bruins defenseman Zdeno Chara is the club's best all-around player, but Claude Julien's club enters Round 2 with injuries to fellow blueliners Andrew Ference and Dennis Seidenberg. Those missing pieces could allow New York to make life difficult for Boston goaltender Tuukka Rask, who posted a 2.49 GAA and .923 save percentage in Round 1 against Toronto.

Expect this series to be marked by low-scoring, close contests and don't be surprised to see a couple of games head to overtime. In the end, "King Henrik" will be the difference as the Rangers get back to the conference finals for a second straight spring.

Rangers in six

WESTERN CONFERENCE

(1) Chicago vs. (7) Detroit

Chicago began slowly in the first round against Minnesota, but the Blackhawks certainly looked like a legitimate Stanley Cup title threat by the time they end the series in five.

With a 24-game point streak to open the season and the NHL's best record, anything short of a trip to the Stanley Cup Finals for the Blackhawks this spring would be a disappointment. Although this battle is against a familiar Original Six foe, the Red Wings are going to have to play a near-perfect series to knock off Chicago.

The Blackhawks won all four meetings in this year's season series and has claimed seven straight against the Red Wings overall. Three of the four encounters between the clubs this season ended after regulation, while the other contest was a 7-1 rout in Detroit on March 31.

Chicago wore down the Wild in Round 1 thanks to its superior depth at both ends on the ice. The impressive roster includes plenty of familiar faces from the Blackhawks' Stanley Cup championship team of 2010. Forwards Patrick Kane, Jonathan Toews, Marian Hossa, Patrick Sharp and Dave Bolland, and defensemen Duncan Keith, Brent Seabrook and Niklas Hjalmarsson all helped Chicago lift the Cup three years ago and head coach Joel Quenneville is leaning heavily on that postseason experience this spring.

Detroit, meanwhile, is a team in transition since the retirement of captain and seven-time Norris-winning defenseman Nicklas Lidstrom. The Red Wings still have star players in forwards Pavel Datsyuk and new captain Henrik Zetterberg, but depth is an issue for this team making its 22nd straight appearance in the playoffs.

Chicago boasts superior horses at both ends of the ice and should be able to dictate the pace against the Red Wings. Detroit needs goaltender Jimmy Howard to steal two or three games if it expects to make it to the next round and the Blackhawks have too much firepower to make that a likely scenario.

Chicago in six

(4) Los Angeles vs. (5) San Jose

Although it may not have the traditional hockey market credibility of Round 2's Original Six battles, this matchup between Pacific Division rivals has the potential to be the most entertaining clash of the conference semifinals.

In one corner you have the defending Stanley Cup champion Kings. In the other is a San Jose club which has been a championship contender for years but has never been able to put it all together.

As the Western Conference's eighth seed a season ago, the Kings knocked off the Vancouver Canucks, St. Louis Blues, Phoenix Coyotes and New Jersey Devils to win their first Stanley Cup championship and did so without home-ice advantage in any of the four rounds. Los Angeles also opened up the 2013 postseason on the road with a rematch against the Blues and dropped the first two games of the series in St. Louis before rebounding to win the next four contests.

In this series, the Kings get to open a playoff set at home for the first time since 1992 and that advantage could loom large in this series. Los Angeles was 19-4-1 as the host this season and has won 10 straight on home ice, having not lost at the Staples Center since March 23.

San Jose won both road games in its first-round sweep of Vancouver, but struggled to a dismal 8-14-2 away mark during the regular season.

The Sharks' best bet to win this series is on the power play, where it scored on nearly 30 percent of its opportunities in the first round. Rising sniper Logan Couture is extremely dangerous on the man advantage for San Jose, but the Kings are one of the NHL's top penalty-killing teams and should have the solution to slowing down the Sharks.

Considering no team has won consecutive Stanley Cup titles since Detroit in 1997 and '98, the Kings will find repeating as champion a difficult task to complete. Still, head coach Darryl Sutter has a roster that's nearly identical to last season's magical playoff run and that should be enough to get L.A. past the Sharks as it earns another trip to the Western Conference finals.

Kings in six