Sens stun Pens

One game, and the Pittsburgh Penguins already know this. Nothing comes easy for a defending Stanley Cup champion, not even a playoff series opener against a seemingly overmatched opponent.

Ottawa Senator Erik Karlsson scores on Pittsburgh Penguins goalie Marc-Andre Fleury during the Senators 5-4 win in Game 1 of their playoff series in Pittsburgh on Wednesday.

Ottawa Senator Erik Karlsson scores on Pittsburgh Penguins goalie Marc-Andre Fleury during the Senators 5-4 win in Game 1 of their playoff series in Pittsburgh on Wednesday.

Senators 5 Penguins 4

PITTSBURGH — One game, and the Pittsburgh Penguins already know this. Nothing comes easy for a defending Stanley Cup champion, not even a playoff series opener against a seemingly overmatched opponent.

Erik Karlsson and Chris Kelly scored on power plays in the second period and the Ottawa Senators ignored their underdog tag and Pittsburgh’s recent playoff success, surprising the Penguins with a 5-4 victory in Game 1 of the Eastern Conference first-round series Wednesday night.

“Nobody’s picking us to win the series,” Ottawa forward Jason Spezza said.

Evgeni Malkin scored twice following penalties on Peter Regin, the first barely three minutes into the game, but the fourth-seeded Penguins looked mostly flat and uninspired for long periods in beginning their bid to become the NHL’s first repeat champion since Detroit in 1998.

“We can’t hang our heads and just say something (like) ‘We didn’t execute,”’ forward Alexei Ponikarovsky said. “We just have to do a better job. We’ve got to work and win the rest of them.”

Sidney Crosby, who piled up 15 points in his final five regular-season games, had three assists but was held without a shot until getting two in the third period. Ottawa constantly matched shutdown defencemen Anton Volchenkov and Chris Phillips against the Crosby line.

With their star so tightly covered, the Penguins — seemingly unsettled by Ottawa’s defensive pressure — were held to a single shot during a stretch lasting 21 minutes 53 seconds following Malkin’s first goal.

The Senators, one of the biggest underdogs of the first-round, went from being down a goal to being up 3-1 during that period as Regin, Chris Neil and Kelly scored — quieting a standing room crowd of 17,132 that clearly arrived expecting another long playoff run by the home team.

“For sure we’d like to get to their d-men and have some speed through the neutral zone, but that starts in other places, too, and we have got to get there,” Crosby said.

Goalie Brian Elliott gave up four goals on 21 shots in his playoff debut, but made several big stops on Ponikarovsky and Malkin in the second period as the Penguins pressed to tie it following Malkin’s second goal, at 10:22.

Instead, the 19-year-old Karlsson restored Ottawa’s two-goal lead less than three minutes later, collecting a rebound of a shot from the left point by Matt Cullen that rebounded off Mike Fisher in front and wristing it into a wide-open corner of the net to make it 4-2.

No coincidence, the Senators said, that rookies Karlsson and Regin scored in their playoff debuts.

“They just feed off one another, if one scores, the other one’s got to score to match,” Neil said. “They room together, they’re inseparable. We call them the twins.”

On this night, they were twice the trouble for Pittsburgh.

Craig Adams and Alex Goligoski also scored for Pittsburgh while former Penguin Jarkko Ruutu also scored for Ottawa.