LAS VEGAS — The Vegas Golden Knights’ incredible inaugural season isn’t slowing down in the Stanley Cup Final.

Tomas Nosek scored the tiebreaking goal midway through the third period, and the expansion Golden Knights opened an improbable Final with a thrilling 6-4 victory over the Washington Capitals on Monday night.

Marc-Andre Fleury made 24 saves in an occasionally shaky performance, but the three-time Stanley Cup winner’s new teammates carried the goalie who has so often carried them with a relentless outburst of offense.

The Eastern Conference champion Capitals hadn’t given up this many goals in 29 games since March 18, but they hadn’t seen anything like this charmed run by the upstart Knights.

“We put fun ahead of everything, and you can tell,” said Ryan Reaves, who scored the Knights’ tying goal in the third period. “Guys have are having fun and they’re smiling.”

With its sellout crowd of hometown fans at deafening volume all night, Vegas put its usual speed and relentlessness on full display while overcoming a third-period deficit to win the opener of a matchup between two franchises seeking their first Stanley Cup titles.

The Game 1 winner has won the last six Cups and 61 of 78 overall.

Braden Holtby stopped 28 shots for the Capitals, whose first Stanley Cup Final game in 20 years was a defensive nightmare. after