PITTSBURGH — First the Capitals, now the Penguins. The Canadiens, the worst-record team in the playoffs, keep sending home the NHL’s best.

Brian Gionta had two power-play goals, Mike Cammalleri scored his seventh goal of a series in which he upstaged Sidney Crosby and Evgeni Malkin and Montreal built a stunning four-goal lead before beating the Penguins 5-2 in Game 7 of the Eastern Conference semifinals Wednesday night.

Believe it, Canadiens. Disbelieve it, Penguins.

Montreal, about the last team anyone would have picked to beat the top-seeded Capitals, much less the reigning NHL champion Penguins, accomplished what no team has done since the current playoffs format was adopted in 1994. And that’s beat the Presidents’ Trophy winner and Stanley Cup champion in successive rounds as an eighth-seeded team.

“We played Washington and we were supposed to get killed and we played these guys and we were supposed to get killed,” defenseman Hal Gill said. “It’s nice to be part of a team that gets things done.”

When it ended, the Canadiens crowded around goalie Jaroslav Halak, who made 37 saves in a performance not quite as dominating as that in Montreal’s 2-1 elimination win of Washington but one that shut down the NHL’s oldest arena.

t, ’Let’s make sure we play the last game at this rink,”’ Cammalleri said. “That’s a cool piece of history for us.”