PHILADELPHIA -- Jake Guentzel scored four goals, and the Pittsburgh Penguins advanced to the Eastern Conference Second Round with an 8-5 win against the Philadelphia Flyers in Game 6 of the first round at Wells Fargo Center on Sunday.
The Penguins, who won their ninth straight series in the Stanley Cup Playoffs, will play the Washington Capitals or Columbus Blue Jackets next. The Capitals lead the series 3-2.
"You get that excitement, a little nerves in you," Guentzel said. "This is what you want to play in. You grew up dreaming about this. It's definitely fun."
[WATCH: All Penguins vs. Flyers highlights | Complete Penguins vs. Flyers series coverage]
Guentzel's four consecutive goals came in a 13:52 span in the second and third periods to give the Penguins a 7-4 lead.
"He has the ability to play his best when the stakes are the highest," Penguins coach Mike Sullivan said. "We've got a number of guys on his team [that can do that] … and I think Jake is one of those guys."
Video: PIT@PHI, Gm6: Guentzel scores four straight in win
Patric Hornqvist and Sidney Crosby each had a goal and two assists, and Matt Murray made 21 saves for Pittsburgh.
Penguins forward Evgeni Malkin did not play because of a lower-body injury he sustained in a 4-2 loss in Game 5.
"All of our injuries throughout the course of the playoffs are day to day, so we'll update on a daily basis." Sullivan said.
Sean Couturier had a hat trick and two assists, and Michal Neuvirth made 20 saves for Philadelphia.
Couturier said he played the final two games of the series on a torn MCL in his right knee after missing Game 4 (a 5-0 Pittsburgh win).
"The decision was on me," Couturier said. "I had the support of the staff, the organization and the medical team. They helped me a lot. We had a lot of treatments. It definitely got better over the days, but it wasn't the ideal situation."
Video: PIT@PHI, Gm6: Couturier pots second playoff hat trick
Guentzel tied it 4-4 at 19:06 of the second period, deflecting Olli Maatta's shot from the point. He gave the Penguins a 5-4 lead when he scored 30 seconds into the third period off a pass from Phil Kessel on a 2-on-1.
Guentzel extended the lead to 6-4 at 12:48 before scoring his fourth straight goal 10 seconds later on a 2-on-1 to make it 7-4.
"I just think [Guentzel] always plays best when the game is on the line," Hornqvist said. "He's been through a lot this year, and he always has a great response when things don't go his way. … He just raises his game. It's incredible to do what he did today, scoring four goals. He was the difference."
Couturier cut it to 7-5 on a rebound in front of the crease at 17:07. Bryan Rust scored an empty-net goal to make it 8-5 at 19:29.
"Looked like we were in control of the game and they got two quick goals there and I'm not too sure (what happened)," Flyers forward Claude Giroux said.
Couturier gave the Flyers a 1-0 lead at 2:15 of the first period. Crosby scored on a rebound off Kris Letang's shot from the point to tie it 1-1 at 6:30.
Carl Hagelin scored for Pittsburgh at 7:17 to make it 2-1 before Andrew MacDonald tied it 2-2 at 15:48.
Couturier scored 40 seconds into the second period to give the Flyers a 3-2 lead. Scott Laughton beat Murray short side from the left circle at 12:14 to make it 4-2.
Video: #ThirstForTheCup: Penguins advance to Second Round
Goal of the game
Guentzel's goal 30 seconds into the third period.
Video: PIT@PHI, Gm6: Guentzel puts Penguins ahead in the 3rd
Save of the game
Murray's save on Shayne Gostisbehere at 12:08 of the third period.
Video: PIT@PHI, Gm6: Murray absorbs Gostisbehere's blast
Highlight of the game
Guentzel's two goals in 10 seconds in the third period.
Video: PIT@PHI, Gm6: Guentzel pots two 10 seconds apart
They said it
"By no means are we satisfied. We're going to try to get some rest here and be ready for our next opponent." -- Penguins coach Mike Sullivan
"Early in the series we didn't play our best. Today we let a two-goal lead slip. Shouldn't happen in the playoffs, but we'll learn from it and come back better next year." -- Flyers forward Sean Couturier
Need to know
Guentzel is the third player in NHL history with four consecutive goals in a playoff game, joining Tim Kerr (Flyers; Game 3 of the 1985 Patrick Division Semifinals) and Newsy Lalonde (Montreal Canadiens; Game 2 of the 1919 Final). He is the first player to score four goals in a playoff game since Jean-Gabriel Pageau of the Ottawa Senators against the New York Rangers in Game 2 of the 2017 Eastern Conference Second Round. … Hagelin left the game with 10:17 remaining in the second period after a hit by Giroux. Sullivan had no update after the game. … Crosby is the fourth player with 60 multipoint playoff games, joining Wayne Gretzky (103), Mark Messier (77) and Jari Kurri (60). … Couturier's hat trick was the second of his career in the playoffs. He also did it against the Penguins in Game 2 of the 2012 Eastern Conference First Round.
Penguins: Game 1 of Eastern Conference Second Round, TBD
Flyers: Season over
Video: Guentzel scores four to lead Penguins to Second Round
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