Rebuilding teams invariably point to moments of growth.

The Flyers grew more in the past 72 hours than they had in the previous six months.

They learned hard and necessary lessons from a sworn enemy, and they blossomed. Or they hardened. Or both.

The Penguins, in pursuit of their third consecutive Stanley Cup, overwhelmed the Flyers in Games 1, 3 and 4 of their first-round playoff series. The Pens snoozed through a loss in Game 2, but they weren't worried. To be fair, they didn't have much to worry about.

Then something about the Flyers changed, in Pittsburgh, in Game 5, on Friday night.

"We had our backs against the wall," said Sean Couturier, who scored four goals and had two assists in the final two games, which he played on a torn knee ligament. "We gave it all we had."

They won Game 5, and then they controlled Game 6 on Sunday; but, finally, they wilted, and the Penguins won, 8-5 — but from the long view, that doesn't really matter. This series launched the Flyers toward relevance. They had eight playoff virgins on their roster. Seven played in this series. When Sidney Crosby and Evgeni Malkin came to the Wells Fargo Center for the third and fourth games of the series, some of them froze. So did some of their veteran teammates.

"It seemed like we had our own shackles on in Games 3 and 4 here," coach Dave Hakstol said. "In a lot of those instances, we were our own worst enemy. I think it was real important for our group — it was about pride — that we went back into Pittsburgh and did everything we could to get this series back here to Game 6."

Startlingly, in that Game 6, they took a two-goal lead after 32 minutes, 14 seconds. But, as Couturier said, that's all they had. The Penguins scored five straight goals, which was the fourth time in the series they scored at least four in a row, which, of course, happened in their four wins.

So what? They're built, not rebuilt. When you're rebuilding, and you finish the season with your tank on "E," there is no shame. Over the final 120 minutes of the series, the Flyers threw more hits, won more faceoffs and killed the last six penalties. They lost all three games at home, but they discovered how to play with a controlled abandon.

"There's been a lot of talk [that] we're tight when we play at home," Hakstol said. "We weren't [Sunday]. Our guys couldn't wait to get back here. Ultimately, we came up short of that full 60 minutes."

With Claude Giroux stifled, with Wayne Simmonds limited by injuries he still won't disclose and with Ivan Provorov's left shoulder scotch-taped to his torso — he took a hellish hit late Friday — the Flyers had little chance of lasting a full 60 minutes against the Penguins, even though the Pens played without injured forward Evgeni Malkin. They needed more than Couturier's one-legged magnificence. They needed everything, from everyone, every night, to have a chance.

Now, this iteration of the Flyers knows what every playoff newcomer learns.

Flyers coach Dave Hakstol watches his team take on the Penguins in Game 3 of the Eastern Conference quarterfinal playoffs on Sunday.
YONG KIM / Staff Photographer
Flyers coach Dave Hakstol watches his team take on the Penguins in Game 3 of the Eastern Conference quarterfinal playoffs on Sunday.

No championship pursuit compares to a Cup chase. There is no room to breathe. You play hurt and you play hard and you play with precision and sacrifice. You play every second like your career depends on it, because it might.

Just ask Radko "Two Turnover" Gudas, who is an old hand at giving pucks away; or Provorov, whose first playoff run ended with two late giveaways, and a very bitter taste.

"The third period didn't go the way I wanted," Provorov said, holding back tears.

Gudas didn't say anything. He hid. He knows how much his lapses hurt.

"You have to do it all the time: You have to be consistent in executing under pressure," Hakstol said.

The Flyers further learned that whistles they might hear in the regular season stay silent in the spring. Giroux got cross-checked and Couturier was upended, both within an arm's length of a referee, and … nothing.

"I think there were a lot of penalties in this series that weren't called," Simmonds grumbled.

Lesson: Cup champs get the calls. They also ignore momentum swings.

The Penguins trailed, 4-2, in the second period Sunday, and the Flyers' third and fourth goals might have stymied a lesser team than Pittsburgh. One came as a Pens power play expired, the other was a breakaway, and both were created by Couturier, a guy playing on one leg. The Flyers were elated.

Then the Pens scored those five unanswered goals.

"We got deflated," Scott Laughton admitted. "The [difference] in the series was momentum swings. We've got to handle them better. We've got a younger team that hasn't been through it."

They got better at it. After the Flyers opened the scoring 2:15 into the game, the youth weathered the Penguins' two-goal charge with three straight goals of their own.

"When they made it 2-1 real quick, we did a good job of tying the game and getting momentum back," Giroux said. "We should do that a little more often."

Now, at least, they know what's coming.

"It was extremely important for them to be part of the playoffs and get a little taste of how the level changes," Hakstol said. "And just how fast a playoff series can move."

At the end of this series, over the last two games, they became a very different group of men. Harder. Better.

It happened fast.