At the other end of the rink stood Montreal Canadiens goalie Jaroslav Halak, his arms raised in triumph, his teammates pounding him on the helmet, on the back, everywhere.

With Halak making 41 saves in his latest spectacular, acrobatic performance, and his teammates combining to block a whopping 41 shots, eighth-seeded Montreal held on to beat Washington, 2-1, last night, stunning the Presidents’ Trophy winner by reeling off three consecutive victories to take the first-round series.

“I’m in shock right now. I don’t know what to say,’’ Ovechkin said, his voice low, his eyes staring at the floor of the locker room. “It was great going up, 3-1, in the series. But it’s only one step. We didn’t do it.’’

The NHL’s two-time most valuable player has played in four career playoff series, and each went to a Game 7. Ovechkin and the Capitals are 1-3 in those deciding contests.

The Canadiens are the ninth No. 8 team to knock off a No. 1 in 32 matchups since the NHL went to its current playoff format in 1994 — and the first to come back from a 3-1 series deficit.

“Before the series started, no one gave us a chance to win, not even one game,’’ said Halak, who stopped 131 of Washington’s 134 shots in Games 5-7. “We proved [to] them they were wrong.’’

Montreal defenseman Marc-Andre Bergeron scored a four-on-three goal in the last 30 seconds of the opening period after Norris Trophy finalist Mike Green was sent off for cross-checking. Dominic Moore made it 2-0 with 3 1/2 minutes left, stealing the puck from Green before beating goalie Semyon Varlamov.

Brooks Laich cut Washington’s deficit with 2:16 to go, and the Capitals then got one last power play a half-minute later, but couldn’t connect. It was a fitting end to the series: Washington’s league-leading power play — which converted 25 percent of its chances in the regular season — went 1 for 33 against Montreal.

“Our best penalty killer was our goaltender,’’ Canadiens coach Jacques Martin said.

Halak and Montreal now take on Sidney Crosby and the defending Stanley Cup champion Penguins in the second round, with Game 1 at Pittsburgh tomorrow.

“If that goalie can play the same way as he played the last three games,’’ Capitals coach Bruce Boudreau said, “anything can happen.’’