After a historic night in which four NHL playoff games churned out four different overtime matchups for the first time since 1985, the first round of the postseason swung even more in favor of the underdogs.

The Pittsburgh Penguins are going for a sweep in their run toward a hopeful repeat championship when they take the ice against the Columbus Blue Jackets for Game 4 on Tuesday. But parity and upsets have frequented the other series across the board.

With some on the verge of clinching a second-round ticket and others backed into a corner, here's a look at some of the teams trending up and down entering Tuesday's action:

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The Maple Leafs are giving the Capitals a run for their money. USATSI

Toronto Maple Leafs: Auston Matthews had his first career playoff goal Monday, but more important, the high-scoring talent around him helped make the Maple Leafs a true challenger for the league's No. 1 team, the Washington Capitals. This team entered the postseason with energetic promise but is now playing confident, opportunistic hockey. Don't be surprised if they take the Caps the distance.

Nashville Predators: No one doubted their offensive firepower coming into the playoffs. But no one thought even their decent history against the Chicago Blackhawks would result in a 3-0 series lead, during which Nashville has outscored Patrick Kane and Co. 9-2. The Predators, complete with big games from Filip Forsberg, Ryan Johansen and Viktor Arvidsson, are playing fast and staying on top of the puck.

Ottawa Senators: It's too early to say they've completely swung momentum in their favor against the Boston Bruins, but for a team whose regular-season finish labeled them a "so-so" postseason contender, the Senators have turned in some memorable -- and clutch -- performances. Two straight rallies and overtime wins have them squarely in the mix against Bruce Cassidy's rock-solid unit, and the big play from their defensemen has been hard to ignore.

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Alex Ovechkin Capitals
Alex Ovechkin and the Capitals are being tested early in the playoffs. USATSI

Washington Capitals: Just because the Maple Leafs own a 2-1 series lead does not mean the Capitals are locked in for another disappointing playoff exit. But it does mean the Presidents' Trophy winners are in trouble. The tell-tale sign that Washington, which edges Toronto in talent but is outgunned in momentum, is stumbling its way through the series: With a 5-on-3 advantage in Monday's OT loss, Alex Ovechkin and Co. could not put a dent in the Maple Leafs' net.

Chicago Blackhawks: Their downfall has been sharper and more surprising than the slide of the Caps. A 3-0 series deficit says it all, but the fact that Kane, Jonathan Toews and the rest of Chicago's seasoned postseason heroes are being completely outworked to the puck is even more concerning. Nashville's five-man units are just getting more done than the Blackhawks, and while nothing is impossible, including a rebound this week, the Western Conference's No. 1 team isn't playing with a lot of life.

New York Rangers: Consider them trending downward but only slightly, mainly because their series with the Montreal Canadiens is almost assuredly headed for seven games. The Rangers have a lot of firepower and could still very well regain the series lead over the Habs, but it's their struggles at home that leave them on a little bit of a slide. They've now lost six straight postseason games in New York, and if another Canadiens surge comes Tuesday night, the Rangers' offensive prowess could face a tall task in getting the series back even.