Trent Frederic’s parents were in attendance Tuesday at Boston’s TD Garden for his NHL debut, and they were not disappointed, even though he received a five-minute penalty for fighting. The 20-year-old Bruins center happened to win that fight, and he left the ice to cheers from the home crowd — and a joyous celebration by his mom and dad.

Cameras caught the proud couple botching a high-five but otherwise delighting in the pugilistic display from their son, who landed several punches on the Jets’ Brandon Tanev before the Winnipeg player fell to the ice and officials stepped in. After the game, a 4-3 shootout loss for his Bruins, Frederic said of his parents, “Obviously, a fight isn’t as cool as, maybe, like a goal or something, so I can only imagine what they’d do then.”

The Bruins selected Frederic in the first round, 29th overall, of the 2016 NHL draft but the St. Louis-area native spent the next two seasons playing for the University of Wisconsin. A standout performer for the Badgers, Frederic went pro in 2018 with the Providence Bruins of the AHL and after establishing himself as one of the organization’s top prospects, he got a promotion Tuesday and quickly won the hearts of Beantown fans.

“Oh, look at him go! Welcome to Boston, Trent Frederic!” exclaimed NESN announcer Jack Edwards, as the 6-foot-2, 203-pound center rained blows upon Tanev. “Just rock 'em sock 'em robots — listen to the crowd at TD Garden!”

Meanwhile, Frederic’s mother and father, clad respectively in a Bruins and a Red Sox hat, were shown clapping, pumping their fists and high-fiving and hugging people around them. “It’s a lot of emotion, and they’re just pumped, and I’m pumped to have them in my corner,” he said.

Frederic is not projected to become a first-line center, but the Bruins have hope that he can anchor a second or third line and provide energy and scoring upside, as well as toughness. The day before the game, Frederic had actually foreshadowed events by telling Boston Sports Journal, “It’s not what I’m trying to be, just a drop-the-gloves guy. But yeah, I’m willing to do it.”

The contest had added meaning for Frederic because he got to skate on a line with Bruins veteran David Backes, who began his career with the St. Louis Blues and was a childhood hero of his rookie teammate. “I try not to be too star-struck to him,” Frederic said before the game (via “But I’m sure he has a clue.”

One clue arrived Monday in the form of a photo that circulated online, showing a nine-year-old Frederic posing with Backes as both wore Blues jerseys. “He’s a good kid with a good head on his shoulders,” Backes said. “If I can give him a little direction, just let him do his thing, I think it’ll be a successful debut for him.”

A successful debut it was, to judge from the roar of the crowd and the approving reaction from Frederic’s teammates.

“It was good to get my feet wet. It lived up to the hype of a first NHL game,” he said after the game. “It was a lot of fun.”

It was certainly fun for Frederic’s parents, who didn’t seem at all fazed by the sight of their son trading punches with another man. It’s fair to wonder how they might have reacted had he gotten the worst of it, but as things turned out after Frederic dropped his gloves, they got a huge lift.

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