Then Marino, 22, took his penalty. This was the last thing the Penguins needed.
"Not (thinking) good things," Marino said of that moment.
The Penguins penalty kill did its job. And as the clock wound down on both the penalty and the period, Marino stood up awaiting his release. An errant pass by the Bruins eluded defenseman Charlie McAvoy and the puck glided toward the penalty box.
Marino stepped out, corralled the puck and put his head up. There was nothing standing between himself and Bruins goaltender Jaroslav Halak.
"I was able to get a fortunate bounce," Marino said. "I skated as fast as I could to get away from the defender. Then I just kind of reacted."
Marino carried the puck into the zone, deked to his backhand and then tapped the puck through the outspread legs of Halak for his first career NHL goal, in his home city, against his boyhood team, with 40-plus friends and family in attendance. And for even more dramatic effect there was only 2.6 seconds remaining on the clock.
Video: PIT@BOS: Marino slips puck five-hole for first goal
"It worked out," Marino said quietly in the locker room following the game.
Marino became the first Massachusetts native since Jim Fahey to score his first NHL goal against the Bruins in Boston (Dec. 23, 2002).
These are the scripts from which Hollywood movies are made. And Marino is living a Hollywood dream 22 years in the making.
As John Marino sat in the penalty box, Cameron Gornet whispered a prophecy for the future from above the Pittsburgh end zone.
"He's going to come out of the box and score," said Gornet, a goaltender at Harvard and Marino's teammate for three seasons.
The recipient of that forecast was Paul Marino III, who also happens to be John's "older" twin brother.
"Knowing Johnny, I was like there's no way that's happening," Paul III laughed. "But he got the puck and I thought Charlie (McAvoy) was going to catch him. I couldn't believe it. It took a good few seconds after the ref pointed for me to realize what was going on."
The suite erupted in cheers that were audible from the other end of the press box. Huddled together in that suite were many friends, former teammates and family members of John Marino. Of course, that included his brother, father, Paul Marino Jr. and mother Jennifer.
"It was great to watch. It was an amazing experience to watch him get his first goal," Jennifer said with a smile. "To see him be able to get it like that was great,
She paused, then added: "And in Boston."
The Marino family hails from North Easton, Massachusetts, which is south of Boston. Both boys started playing hockey at a young age by freak accident. Paul III was born with bowed legs, and as a cure, a doctor suggested he try ice skating.
So, both Marino boys began skating before their second birthday. And playing hockey wasn't far behind. John excelled immediately according to his parents. He would go on to star for his Tier III junior club, South Shore of the United States Premier Hockey League (a team that also featured Noah Hanifin and Colin White).
John's play caught the attention of the Edmonton Oilers, who drafted him in the sixth round (154th overall) of the 2015 NHL Draft. He played one season (2015-16) for Tri-City of the USHL, helping lead his team to the Clark Cup championship. John came back home for college, attending prestigious Harvard University.
John made the decision to leave Harvard after his junior season and begin his NHL career, landing in Pittsburgh. He has earned a regular spot in the Penguins lineup, and had a proper homecoming in his hometown of Boston.
And his family has been with him every step of the way.
"I've been watching him his whole life," Paul III said. "Just to see the culmination of all the hard work pay off, it's really something special. It's something that not many people get to experience and I'm very thankful I get to experience it."
"He's just worked so hard for this," Jennifer said. "Early mornings, working hard, missing time with friends. For it all to come together and have the opportunity to play for Pittsburgh is just a dream come true. … It's definitely a thrill for us."
It takes a village to raise a hockey player. And many of those people who were so influential in John's life both as a hockey player and as a person were on hand to witness him realize his dream and play the game that he loves. Oh, and score his dramatic, milestone goal.
"It's an amazing experience," Jennifer said. "It's great that it happened here in Boston, in his hometown. His friends are here, his teammates are here from Harvard. It's a really special experience for us."
The lifetime scout
Penguins special assignment scout Kevin Stevens had his eye on John Marino for a long time. A really long time. Marino and Stevens' son, Luke, played on the same youth team. And one of those teams was actually coached by Stevens himself.
"It's nice when you watch a kid grow up," Stevens said in the TD Garden press box Monday night. "I know him. He's a great kid. That's half the battle. You want someone that wants to learn. He wants to learn. He has upside. He's a good person. That's most important."
Stevens followed Marino's career from youth to South Shore - where Marino was once again a teammate with Luke - and to finally Harvard. It was at the Ivy league school that Stevens really took note of his game.
"He's a steady defenseman. You saw the potential in him," Stevens said. "Good skater, sees the ice well, pretty simple guy. He should have a great career."
When it became clear this summer that Marino wasn't going to sign with Edmonton, Stevens spoke with Penguins director of player development Scott Young and amateur scout Frank Golden about his potential.
"We were all on the same page about him," Stevens said. "He had an upside. That's what you want in a defenseman."
From there they lobbied general manager Jim Rutherford to acquire him. Rutherford acquiesced and for a sixth-round pick in 2021, the Penguins acquired his rights in late July.
"Jim trusted us. He made a move," Stevens said. "We were able to get him. It was a good pick up for us."
In early August, Marino made the decision to sign an entry-level contract with Pittsburgh and forgo his senior season at Harvard. And Stevens knew that entering training camp Marino had a real shot at making the team despite his youth and lack of experience.
"I thought he had a chance to play," Stevens said. "I watched him at Harvard the last couple of years. I knew what type of player he was. It's very hard to jump in and play in the NHL coming out of college. Not many guys do it."
Marino's play during training camp so impressed the coaches that they opted to keep him in the NHL to start the season despite having nine defensemen on the roster. He was a healthy scratch in the first two games of the year. But on Oct. 8 against Winnipeg Marino made his NHL debut.
He hasn't looked back since.
"I've liked a lot about his game," Penguins head coach Mike Sullivan said. "He's a real good defender, he's a strong skater, he closes on people as good as any defensemen we have, he's got a good stick.
"What's really impressed us is his ability to make outlet passes. He has poise with the puck. He finds that little pocket option in the center under pressure pretty well for a guy that's new to the league. He's getting better with every game that he plays."
With every game that he plays the coaching staff is leaning more and more on him. He averages anywhere between 16-18 minutes a game, and has twice played in over 20 minutes of action.
"He's done a pretty good job for us," Stevens said. "Consistency is the biggest thing in the NHL. You have to be ready to play every game. There are no nights off. You have to prepare yourself to play. I think he's done a good job of that. Now, it's just about getting better and working on his stuff.
"He's only going to get better."
"Something I'll always remember."
Growing up so close to Boston, Marino was raised on New England sports. And as a hockey player, his fandom gravitated toward the Bruins.
"I grew up watching the Bruins and going to games when I was growing up," Marino said. "I still remember the (2011) Stanley Cup run and playoff experiences after that and going to all the games."
The first time Marino skated on the ice surface at TD Garden, he was wearing a Harvard jersey. It was his freshman season in 2016-17 and his team was playing in the historical Beanpot Tournament.
Marino helped the Crimson capture their first Beanpot title since 1993 by chipping in an assist in a 6-3 victory against Boston University.
"That was pretty cool," Marino said, "especially on this ice, it was packed here. That was a special experience."
Marino added a new special experience to his hockey career on Monday night. It was a dream to skate on the same ice surface as many of his childhood idols, and to play against some of them - Patrice Bergeron, David Krejci, Brad Marchand, Zdeno Chara, Torey Krug and Tuukka Rask.
Next to winning a Stanley Cup, it's every childhood hockey player's dream. And to score a big goal at a big time only made the moment that much sweeter.
"Our players and coaching staff were thrilled for him," Sullivan said. "That's an exciting moment for a player when he comes to his hometown. Your first time back in your hometown playing in the NHL is a special moment."
It was a magical moment for Marino and his entire entourage.
"That was something special," Marino said. "It's something I'll always remember."