The Vegas Golden Knights were having enough problems solving Thatcher Demko. Then came another big obstacle — a major penalty that brought back memories of the team's collapse in last year's postseason.

“You've got to think it crossed our mind a little bit,” Vegas forward Jonathan Marchessault said. “Every team, we're going to face adversity — a hot goalie, or a five-minute major or something like that, but our team was able to kill it off.”

The Golden Knights withstood a major penalty and ejection to Ryan Reaves in the second period, and Shea Theodore finally put the puck past Demko in the third, lifting Vegas to a 3-0 win over the Vancouver Canucks on Friday night in Game 7 of the second-round series.

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Theodore’s goal with 6:08 remaining was the first in 138:40 for the Golden Knights against Demko, the rookie goalie who had brought Vancouver back from a 3-1 deficit in the series and held off Vegas for most of this game, too.

“There was times it felt like we could have played for six hours and not scored on him,” Golden Knights coach Peter DeBoer said.

Theodore scored a power-play goal on a wrist shot from the blue line that slipped through traffic and past Demko, who had made 98 consecutive saves. Alex Tuch and Paul Stastny added empty-net goals.

“That's a good hockey team. They beat us tonight and deserved to win,” Canucks coach Travis Green said. “Our goalie gave us a chance to win.”

The Vegas goalie was pretty good too. Robin Lehner tied a record with his third shutout of the series, and his sensational glove save on Brock Boeser in the second period kept the game scoreless.

Vancouver missed an opportunity when it failed to convert on an extended power play after Reaves was ejected with 3:30 remaining in the second. He received a major penalty for a hit to the head of Tyler Motte, but that power play — which extended into the third period — was fruitless.

The call on Reaves was less controversial than the penalty that sank Vegas last season. In Game 7 of a first-round series against San Jose, the Golden Knights were up 3-0 when Cody Eakin was given a major penalty for cross-checking. The Sharks scored four quick goals and eventually won in overtime.

DeBoer was actually coaching San Jose in that game.

“Now that you bring that up, five-minute major, right? Penalty killing in a Game 7. That's familiar, I'm sure,” DeBoer said when asked about the long Vancouver power play. “PK was great. Robin Lehner was great."

Vegas outshot the Canucks 36-14 in this game and 127-54 over the final three. It was barely enough. The Golden Knights will face Dallas for a berth in the Stanley Cup final. It would be the second trip to the final in the three-year history of the Vegas franchise.

The Golden Knights outshot Vancouver 91-40 in Games 5 and 6 but managed only one goal in that span. It was all Vegas again at the start of Game 7, but the Canucks withstood the initial push and made it to the end of the first period in a scoreless tie. The Golden Knights had an 11-2 edge in shots.

“I felt great the whole game. No fatigue,” Demko said. “I had a lot in the tank.”

Reilly Smith missed the net on a breakaway early in the second for Vegas, and the best save of that period actually belonged to Lehner. As he has for most of these playoffs, he got the start over Marc-Andre Fleury, and when the Canucks produced a rare scoring opportunity on a 2-on-1 break, Lehner made a lunging glove save on Boeser.

“I know you say that I can't save backdoor shots, but big man can move when he wants to,” Lehner said.

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Nicolas Roy beat Demko to the glove side with about 12 minutes to go, but the shot hit the post. Then Vegas easily killed off another Vancouver power play as it became increasingly clear that the first goal would probably decide it.

Vancouver's J.T. Miller was called for hooking with 6:13 remaining, and Vegas needed only a few seconds to score.

NOTES: With the Canucks out, Canada again won't have a Stanley Cup champion. The last team from Canada to win it all was Montreal in 1993. The last to reach the final was Vancouver in 2011. ... The last goalie with three shutouts in a playoff series was Michael Leighton of Philadelphia, against Montreal in 2010.