Like a lot of people who reach a certain age, Rutger McGroarty had a story to tell about his 21st birthday.

He wore different skates.

As in, one skate was older and broken in while the other was brand new and probably still a little stiff.

That misadventure happened to the Pittsburgh Penguins rookie forward Sunday during a 1-0 overtime home win against the Ottawa Senators.

“I had on two different skates,” said McGroarty, who reached that celebratory age of 21 on Sunday. “My skate broke on the last shift. (Penguins defenseman Erik Karlsson) took a slap shot and it hit off my skate, and I thought my blade just fell out. But my whole holder snapped.

And so (head equipment manager Jon Taglianetti) rushed back, grabbed my backup pair of skates. So, I’m wearing two different skates. They’re brand new. First time ever putting them on.”

The exuberance of telling that tale — volunteering it without solicitation from a reporter — is reflective of the youth and vigor McGroarty and fellow rookie forward Ville Koivunen bring to a roster mostly stocked with veterans.

Each player was recalled from Wilkes-Barre/Scranton of the American Hockey League (AHL) on Friday.

“When you have young players that are excited to be in the NHL, they’re excited to be part of an NHL dressing room and be part of the Pittsburgh Penguins, I think that energy is contagious,” coach Mike Sullivan said. “And that’s what these guys are bringing. They’re really excited to be here. Obviously, it’s a big deal for these guys and it’s a big deal for us as an organization. They’re deserving of being here.”

McGroarty appeared in his fourth NHL game Sunday after skating in three contests in October. As for Koivunen, he made his NHL debut and was subject to the customary “rookie lap” where a first-time NHLer is expected to skate around the defending zone of the rink by himself before his teammates join him for warm-ups.

“I was a little bit nervous, but luckily, I didn’t fall,” Koivunen quipped. “So, I was happy with that.”

By just about any measure, there was plenty to be happy about with both players on Sunday.

McGroarty opened the contest on the top line and logged 16:57 of ice time on 25 shifts and had three shots on five attempts.

His center offered a strong assessment of the 6-foot-1, 203-pound winger.

“He played well,” Crosby said. “He was in on the puck, in on the forecheck, created turnovers, had a couple of chances in around the net. He competed really hard.”

Most of his ice time — 5:42 on nine shifts — came in the third period with the game scoreless. Typically, rookies don’t get an abundance of trust in situations like those.

“That’s something that I take a lot of pride in, my full 200-foot game and being trustworthy in the (defensive) zone and also the offensive zone,” McGroarty said. “It means a lot, and it was really cool to be out there.”

Koivunen (5-foot-11, 161 pounds) skated on the second line and logged 17:28 on 25 shifts while firing two shots on seven attempts.

“Ville, I think, is a smart player that sees the ice real well,” Sullivan said. “Plays a pretty good give-and-go game. I was curious to see how Ville would do with the pace and the size of the NHL and I thought he handled it extremely well. I look forward to watching him more.”

Koivunen indicated it didn’t take him long to adjust to the pace of the NHL game.

“I think after the first shift, like, I felt so good right away,” Koivunen said. “I was like ‘Yeah, I think I can play here.’”

McGroarty and Koivunen will likely play the remainder of the regular season on the NHL roster before returning to Wilkes-Barre/Scranton to lead that team’s efforts in the AHL’s postseason.

They’ll take back plenty of stories they can tell to anyone who will listen.

“I love my parents and my sister and my girlfriend,” McGroarty said. “But no present they’ve ever got me could live up to that.”