On the Pittsburgh Penguins team plane, John Marino challenges Sam Lafferty in Wordscapes, a fast-moving game they play on their mobile devices. They swipe different letter combinations into words, filling small crossword puzzles and earning points.

If this sound like something a Harvard student would play to pass the time on a team flight, that would be correct. If this sounds like something two NHL rookies would partake in while the veterans are dabbling in other pastimes on that same flight, that would also be correct.

"I don't think I've graduated to the card table yet. But maybe one day," Marino, 22, told ESPN last week.

This is Marino's first NHL season, but you wouldn't know it from the way he has played. Thrust into a prominent role thanks to the team's mounting injuries, Marino has 13 points and a plus-12 rating in 28 games while averaging 19:34 on the ice per contest. He's on the positive side of shot attempts at 5-on-5, and has an expected goals percentage of 58.94. While fellow rookie defensemen Cale Makar and Quinn Hughes have gotten all the attention, Marino is quietly having one of the finest campaigns for a first-year blueliner this season.

Not bad for someone who made the leap from Harvard to the NHL, without spending a minute in the minor leagues.

"It's a significant jump. Just in the logistics. The amount of games that you play, in and of itself, is an adjustment [in making] the jump from college to the pros," Penguins coach Mike Sullivan said. "But John's done a great job. He's gotten better since the beginning of training camp. He's earned his way onto this roster, and he continues to earn his way onto this roster."

The learning curve is steep for any rookie, but even steeper for a rookie defenseman.

"Adjusting to the fast pace, learning what works and what doesn't," said Marino, "but you figure that out quickly at this level."

His college coach has been impressed how fast Marino has figured that out.

"There was no question in my mind that John is a National Hockey League player," said Harvard men's hockey coach Ted Donato. "But I've been a little surprised by how quickly he's been able to adapt."

Also surprising: How Marino ended up in Pittsburgh.

Born just outside of Boston in North Easton, Massachusetts, Marino's first big move on the road to pro hockey was to Nebraska.

In 2015, he relocated to Kearney to play for the Tri-City Storm, a Tier 1 junior team. It took him some time to adjust to the new culture, to the new team and to public high school life.

He made a quick impression on NHL scouts. Central Scouting said "when Marino fills out his frame he shows the potential to be a dominant two-way defenseman" in ranking him No. 63 on its top 100 draft prospects list in 2015. In the NHL draft that year, the Edmonton Oilers selected him No. 154 overall.

After one season in the USHL, he committed to play at Harvard in 2016.

"Honestly, not many of the students there probably are even aware there's a hockey team on campus. Hockey comes second there for most people. If not, third or fourth. Once you're away from the rink, you're away from that hockey lifestyle. So that's nice to have," Marino said.

"There's a ton of athletes on campus. You all kind of get along. There's not one sport that stands out. Everyone's on equal footing because no one, I would say, is really concerned too much about the athletics. A lot of people realize that you're not going to be playing in athletics forever."

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Marino played three seasons with Harvard, scoring 42 points in 101 games. He was a shutdown defenseman, and Donato had no problem sending him out against the top talent on other teams.

"He's outstanding in breaking the puck out. He has the poise to make the reads that a defenseman has to make. I compare it to a quarterback understanding what's coming at him," said Donato. "He was a pleasure to coach because he just showed up, played very hard. Never looked tired. Never complained. Just a great teammate on top of being a great player."

As his game improved, the next decision for him grew closer: Would he sign with the Oilers, remain at Harvard for another season, or was there another path to take?

"Their prospect pool was pretty loaded," Marino said of his decision to not sign with the Oilers. "I was planning on going back to school. Then the trade to the Penguins happened."

The Penguins acquired Marino in July for a 2021 sixth-round draft pick. "John is a mobile defenseman who excels at moving the puck while also playing with an edge to his game," Penguins GM Jim Rutherford said at the time. "We are excited to acquire him as we continue to add defensive depth to the organization. The next step is to work on getting a contract done with him."

He signed an entry-level deal with the Penguins, forgoing his last year at Harvard for a shot in the NHL.

"They said that 'he's a guy that's going to challenge for your lineup,'" said Sullivan, "and they were right."

Marino's ice time has increased as the season continues. Keith Gillett/Icon Sportswire

The Penguins aren't too far removed from their last Stanley Cup championship in 2017. Sidney Crosby, Evgeni Malkin, Kris Letang and others remain the veteran core of that dressing room. These were players Marino grew up watching. Now, without having played a single minute at any other level of the Penguins' organization, he was their teammate at 22 years old.

"You try not to think of it too much, with all of those names on the wall. Crosby, Malkin, Letang ... all of them. There's so much experience in that room," he said. "But the culture's set up there to help you. All that experience plays to your advantage. You just want to take in as much as you can and learn from the older guys."

Even when one of the older guys is Sidney Crosby.

"You just try to treat him like another teammate. As difficult as that may be sometimes," Marino said.

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His transition was made smoother by the Penguins' defense corps, which Marino said is "really close." He played earlier in the season with Jack Johnson, whom he described as "awesome." He and Brian Dumoulin -- who was born in Biddeford, Maine, and played at Boston College -- bonded over their ties to Boston. He and Justin Schultz have talked about what could have been for both in Edmonton, as Schultz was once an Oilers defensive prospect, too. He did his best to hang with Letang as his partner.

"You can't really try to do what he does. He's incredibly talented," Marino said. "The game seems to come so easy for him. But he's pretty easy to play with. You know once he has the puck, he's going to make a good play."

Marino has earned these opportunities with steady play, but also because the Penguins have been besieged by injuries. Letang (22 games played), Dumoulin (23) and Schultz (23) have all missed time this season, opening the door for Marino. That the Penguins continue to thrive (17-9-4, and in a wild-card spot) despite these injuries seems, at this point, like it's part of their DNA as a franchise.

"I think it plays to the culture of the organization. They expect wins. Playing the game the right way. It's the next-man-up mentality," Marino said.

And their success has, in a way, opened the door for Marino, as Donato sees it.

"The reality is that with the injuries there and their salary cap situation, in light of the fact that they went to the Stanley Cup Final two years in a row ... they have so many great players, they're trying to make runs to the Stanley Cup, so they might not have the prospect pool that a lower team that hasn't had as much success would have. So that helped with the initial opportunity for John," Donato said.

"But by no means am I trying to take any credit away from how he's playing. Because he's making a transition that's very, very difficult look pretty ordinary."