NHL preview: Among the big questions in Eastern Conference, can Penguins three-peat?

The Pittsburgh Penguins last season became the first team to win back-to-back Stanley Cup championships since the Detroit Red Wings prevailed in 1997 and 1998.

Penguins captain Sidney Crosby pulled off the remarkable feat of being voted the most valuable player of the preseason World Cup tournament — a pale substitute for the Olympics — and MVP of the Stanley Cup playoffs. Crosby, who turned 30 in August, isn’t “Sid the Kid” anymore but he still has many productive seasons left.

Here are the big questions in the Eastern Conference leading into the season:

Can the Penguins pull off a three-peat?

They’ve shown a knack for infusing young players into the lineup in important roles (think Jake Guentzel, Bryan Rust, Conor Sheary and goaltender Matt Murray). They lost quality support players (Nick Bonino, Chris Kunitzand and Matt Cullen) but they have young talent to draw upon and will get a boost on defense from the return of a healthy Kris Letang.

The last team to win three straight Cup championships was the New York Islanders, who won four straight starting in 1980. Barring major injuries, the Penguins have a good chance to continue moving toward the Islanders’ benchmark.

Is the Washington Capitals’ window closed?

Quite possibly. Another Presidents’ Trophy (most team points in NHL) led only to another early playoff exit for the Capitals, who had to part with forwards Justin Williams and Marcus Johansson and defensemen Kevin Shattenkirk, Nate Schmidt and Karl Alzner because of salary-cap considerations. That’s going to hurt a lot. Their quietly excellent goalie, Braden Holtby, is their biggest weapon in avoiding a major backslide. Alexander Ovechkin’s 33 goals last season were his fewest in a non-lockout season since 2010-11. He’s still fearsome, but for how much longer?

Which teams in the East are on the rise?

Auston Matthews had 40 goals for the Toronto Maple Leafs last season and was voted rookie of the year. He’s poised and able to do more — and so are they. The Carolina Hurricanes always seem to have better talent than results but could reach the playoffs after building a mobile, young defense and adding veteran forward Williams.

It might sound strange to call 2015 East champion Tampa Bay a team on the rise, but the Lightning missed the playoffs last season largely because of Steven Stamkos’ knee injury. He has recovered and so will they, aided by the additions of character players in winger Chris Kunitz and defenseman Dan Girardi, and the talent of defense prospect Mikhail Sergachev.

The New Jersey Devils got a good player, if not a generational talent like Edmonton’s Connor McDavid, in No. 1 draft pick Nico Hischier. They also beat out a half-dozen other teams to sign free-agent defenseman Will Butcher after his standout college career. They’ll miss the playoffs but they’re putting some good building blocks in place.

New home, new playoff streak for Detroit?

The Red Wings left Joe Louis Arena and its classic, non-corporate name for Little Caesars Arena, which they’ll share with the NBA’s Pistons. But some traditions endure: Building manager Al Sobotka christened the new building by twirling and tossing an octopus onto the ice. The Red Wings’ 25-season playoff streak ended last spring but they won’t start a new streak in their new home. They’re too creaky in too many key areas and thin on defense.

Can the Ottawa Senators repeat their surprise trip to the East final?

They operated under the radar while eliminating Boston and the New York Rangers and taking the Penguins to double overtime in Game 7 of the East finals. That will be tough to do again. Their biggest star, two-time Norris Trophy (best defenseman) winner Erik Karlsson, is questionable for the opener after foot surgery. So is center Derick Brassard (shoulder). Promising center Colin White (broken wrist in training camp) is out for a while. This could be a very challenging season.

helene.elliott@latimes.com

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