Marc-Andre Fleury made 30 saves for his 11th career playoff shutout, Shea Theodore scored in the first period and the host Vegas Golden Knights beat the Los Angeles Kings 1-0 on Wednesday night to win the franchise's first playoff game.
The expansion franchise will try to take a 2-0 lead in its first-round playoff series Friday.
Fleury got his first playoff shutout since last May, when his Penguins beat the Ottawa Senators 1-0 in Game 2 of the Eastern Conference finals.
Theodore put a wrist shot past Jonathan Quick 2:23 into the game. Quick stopped 27 shots.
The Kings entered with a combined 928 games of playoff experience to none for the Golden Knights.
Pittsburgh 7, Philadelphia 0: The sluggish opening three months. The so-so finish. The only occasional attention to detail on defense. None of it matters anymore.
The playoffs are here. The champs are, too.
Sidney Crosby and his teammates provided proof in the host Penguins' dismantling of the Flyers in the opening game of their first-round series.
Crosby performed more stick wizardry on his way to his third postseason hat trick, Evgeni Malkin added a highlight-reel goal of his own and the Penguins overwhelmed their seemingly overmatched cross-state rivals to begin their quest for a third consecutive Stanley Cup with a blowout that seemed to indicate the grudge match could be a mismatch.
Not that Pittsburgh's captain wanted to buy into any sort of message-sending, even after the Penguins became only the fifth team in NHL history to win a series opener by at least seven goals.
"I mean, it's one game," Crosby said. "Whether it's 7-0 or 1-0 or double overtime, it's one game. A big part in the playoffs is to get better every game and to adjust, and that's the way we have to look at it."
That might be a frightening proposition for the rest of the NHL. It certainly is for the Flyers, who have lost all five meetings with Pittsburgh this season, giving up at least five goals each time. Nothing that happened during the regular season, however, compared to Wednesday night. The Penguins pumped in five goals in the first 29:01 to chase goalie Brian Elliott, and the Flyers simply could not keep pace.
"It was one of the worst games I've been a part of," Flyers forward Claude Giroux said.
Philadelphia coach Dave Hakstol mercifully pulled Elliott after Crosby swatted Brian Dumoulin's point shot out of the air and knocked it by a stunned Elliott to put the Penguins up 5-0 just before the game's midway point. Elliott stopped 14 of 19 shots before being replaced by Petr Mrazek. Mrazek made 12 saves, but Hakstol indicated he's likely to go with Elliott again in Friday's Game 2.
Whoever is in net for the Flyers, it won't matter if the play in front of them isn't better. Philadelphia's power play went 0-for-4 and didn't even generate a shot.
"They beat us from pretty much every aspect [Wednesday], starting from the net out," Elliott said. "Everybody just has to be better."
Former Hill-Murray star Jake Guentzel had a goal and three assists for the Penguins.