Letang drew Pittsburgh even less than 4 minutes later, skating from the point deep into the zone and stuffing it past Budaj for his first goal since Nov. 26, when he scored in overtime. A day later, Letang learned he sustained a concussion following a collision with Pacioretty, leading to nearly two months on the injured reserve.

The defenseman returned Thursday night in a win over the New York Rangers and looked fresh on the second half of a back-to-back.

The same couldn't be said of his teammates, at least through the first two periods.

Pittsburgh played its best game against a quality team all season in dropping the Rangers, leading all the way for a road win that proved their recent surge wasn't simply a product of a soft spot in the schedule.

The Penguins didn't have the same fire against the cellar-dwelling Canadiens, who built a pair of two-goal leads, with the league's worst power-play unit even chipping in a rare goal courtesy of a wrist shot from the slot by Kostitsyn.

When Pacioretty beat Fleury midway through the second to put Montreal up 4-2, it looked as if the Canadiens were on their way.

They weren't, getting outshot 14-7 in the third period to let another lead slip away.

"It's frustrating for everybody," Cunneyworth said. "I mean, we deserved maybe a little better fate for going ahead as we did, but it's a battle out there and I think we have to continue to keep battling hard and work right until the end."

NOTES: Jeffrey's goals were his first since scoring a pair against Boston last March. ... Pittsburgh has outshot the opposition in 13 straight games. ... Defensemen Raphael Diaz and Yannick Weber were scratched by Montreal. ... Defenseman Ben Lovejoy and forwards Jason Williams and Arron Asham were scratched by the Penguins.

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Pens send Sens packing

PHT: Powered by a James Neal hat trick, Pittsburgh dominated Ottawa 6-2 in Game 5 to advance to the Eastern Conference finals.

NBC Sports

Highlights: Penguins crush Senators to move on

  The Pittsburgh Penguins squashed any concept of an upset by a massive underdog in the Ottawa Senators. James Neal led the way for the Pens with a hat trick as Pittsburgh now moves on to the Eastern Conference finals after a 6-2 victory in Game 5.

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