Now the Boston Bruins defenseman stood in a suite with a red-and-white Terriers cap on his head and a slice of pizza cooling on a table nearby, as his former team tried, and ultimately failed, to win a college hockey game.
"It's cool," he said then, of being at the Beanpot on Feb. 12. "It's emotional. It's exciting. It's a little bit weird to be on the other side now, but just as emotional, just as scary watching it."
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His Terriers lost to Harvard in the Beanpot final last season, on what was once a big stage for McAvoy. It is no longer. Now, with one Stanley Cup Playoff series in his past, the 20-year-old faces another, this one as a celebrated rookie in the NHL, a top-pair defenseman on one of the best teams in the Eastern Conference. This one is against the Toronto Maple Leafs, the Bruins' longtime rival, with Game 1 of the best-of-7 Eastern Conference First Round at TD Garden on Thursday (7 p.m. ET; NBCSN, CBC, TVAS, NESN).
It has been little more than a year since McAvoy played in the Beanpot, since he made his home on Commonwealth Avenue as a BU student. It has gone by in the blink of an eye. And yet McAvoy has made the transition with hardly a misstep, as easily as one could, even with injuries and heart surgery thrown in.
"A year ago we were here and we lost to Harvard and that was tough," McAvoy said in February. "For myself personally, it's been kind of a whirlwind since then. A lot has happened."
From the outside, it seemed to take one day. The first time McAvoy faced the media as a member of the Bruins, at Warrior Ice Arena after his first professional practice just before the 2017 playoffs, he seemed a bit daunted, a deer in klieg lights.
The second day? He was fine.
He was ready.
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"His personality and how he handles the moments is pretty unique for that age of player," Boston general manager Don Sweeney said of the defenseman, a first-round pick (No. 14) by the Bruins in the 2016 NHL Draft. "He's never scared of the moment."
He excelled in the playoffs, playing beyond his years and beyond his experience, getting three assists in a six-game first-round loss to the Ottawa Senators while playing the second-most minutes on the Bruins (26:11 per game). It was a remarkable debut, and it foretold of greater potential, of the chance for McAvoy to be the next great Boston defenseman.
It also told of someone comfortable in his surroundings.
"He could have stayed in his dorm," BU coach David Quinn said, half joking. "He could have roomed with his same roommate from last year, lived in Student Village here, and not missed a beat."
Unlike former BU teammates Clayton Keller (Arizona Coyotes) and Jordan Greenway (Minnesota Wild), McAvoy didn't need to head to a faraway NHL city to make his next move. The Long Beach, New York, native simply needed to hop on the MBTA to the Garden, change his address from Brighton to Charlestown, and swap his college roommate for new teammate Anders Bjork.
He's close enough that he can drop by BU occasionally. So he does.
When Quinn walked into the BU dressing room in early February, there was McAvoy, sitting in one of the locker stalls, chatting with his former teammates. He had stopped in to wish them good luck in the Beanpot.
It came just after a bump for McAvoy, when an abnormal heart rhythm that had first popped up when he was at BU came to a head, resulting in surgery Jan. 22 to correct a supraventricular tachycardia, which was not considered dangerous. The problem was corrected, with doctors assuring McAvoy it would not recur after the procedure, and he missed four games from Jan. 23 to Feb. 1. Quinn, among others, visited him at Massachusetts General Hospital.
"I think there's a lot of value there," Sweeney, who played at Harvard and then for the Bruins for 15 seasons (1988-2003), said of McAvoy being near his college team. "I spent a tremendous amount of time at Harvard during my first few years playing. I had a close connection with Jack Kirrane (the former U.S. Olympic hockey player and Harvard rink manager). … To me, that kept things a little grounded and familiar."
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It gave him a sense of normalcy. Sweeney is not alone in that position. Defenseman Matt Grzelcyk also went to BU, and grew up in Charlestown. Forward Ryan Donato is taking classes at Harvard, making the transition from undergrad to professional athlete.
They, like Sweeney, know that the proximity can make things easier.
"That's not a luxury that many people have," McAvoy said.
He doesn't have withdrawal. He doesn't miss it. He doesn't have to.
Not that McAvoy was ever likely to suffer from lack of confidence, even if he had moved to a new city, even if he had to face a new environment on this stage. He comes across as sure of himself, ready for most anything, something those around him have witnessed for years.
"He's just got really good poise, like he's not flustered when he's playing against a guy like [Sidney] Crosby or [Alex] Ovechkin or anybody like that," said Calgary Flames forward Matthew Tkachuk, who has known McAvoy since they played on the U.S. under-17 national team in 2013-14. "He'll step up and play against anybody."
He has had to do just that.
McAvoy has spent most of the season on the top defense pair with Zdeno Chara, helping to rejuvenate the 41-year-old captain and the Bruins defense. McAvoy had 32 points (seven goals, 25 assists) in 63 games, averaging 22:08 per game, leading all NHL rookies who played at least 30 games. The Bruins allowed the fourth-fewest goals per game in the League (2.57), a surprising result for a defense that has relied heavily on three first- and second-year players (McAvoy, 24-year-old rookie Grzelcyk and Brandon Carlo, 21, who is out for the season with a fractured left ankle).
"He plays with so much confidence that just watching him, it kind of makes me be like, I should do something like that," Grzelcyk said. "I think I'm learning from him a little bit even though he's a lot younger than me. … He hit it in stride, obviously. It's insane to see."
Especially because it's happened before.
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When McAvoy arrived at BU at 17, younger than many freshmen, he didn't struggle.
He didn't need time to acclimate. He didn't get overwhelmed mentally or physically. He jumped in and felt at home. He would occasionally try to do too much. But, as Quinn said, that was a forgivable sin.
"Right away, some people have it," Quinn said. "I think it's hard to explain, he has it. He's got the physical tools, he's got the mental tools. He's got swagger. He's fearless. That's when you've got a special player."
But there was one moment when he lost that, when he wavered in the face of pressure, in the face of worry, and when being in Boston came once again to his rescue.
It was last season with the 2017 NHL Trade Deadline approaching. Quinn was shooting pucks with McAvoy in the morning, something that usually was accompanied by laughter and banter and fun. It wasn't that day.
Rumors had been circulating around the city about trade possibilities, including McAvoy going to the Colorado Avalanche as part of a package for forward Gabriel Landeskog. It was getting to the college student.
"It was just a different feel," Quinn recalled. "I could tell there was a lot going on in his head."
Quinn called Sweeney.
Sweeney was there half an hour later.
"Donnie came down and Donnie did a heck of a job talking with him," Quinn said. "Charlie right after that, he played his best hockey ever at BU."
Chara added a photo to his Instagram account April 3, one of him standing next to McAvoy in front of a bunch of hanging Bruins jerseys. Each player was holding a stick. But the important part of the post was in the caption, where Chara wrote, "Power of two generations."
That is what the Bruins had been seeking, ever since their trade of Dougie Hamilton to the Flames on June 26, 2015. They knew that Chara would not be around forever, and that they needed to find an heir.
It appears they have.
"He's such a magnetic personality," Quinn said. "He's very confident in himself, yet respectful. He's not arrogant in any way. … Most rookies with a strong personality probably have to go through some tough times with their teammates and I get the feeling from what I hear that [it] has never been the case with him up there.
"It doesn't hurt that he's damn good."
It also doesn't hurt that he has been allowed to progress in a place that has become his home, down the street from his friends and his coach and the place where he bridged the gap from childhood to adulthood. It doesn't hurt that BU is there, if he needs it, that the transition has not been his whole world.
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"I'm very fortunate for that," McAvoy said. "I'm very grateful for that. It's special, honestly. I don't really know how else to explain it. I got so attached to this city, [during the] recruiting process I decided that I wanted to come to school in this city, this was a city I fell in love with.
"I loved every second that I was [at BU], the surroundings, and then to find out on draft day that I was coming and I was going to be able to play pro [hockey] to start my career and be a part of the Bruins organization was surreal, to know that I could stay here, that whenever I felt like I needed to go I would still be here in the city of Boston, I would still be able to have all those relationships with all those people, my teammates, stay here and still have all the friends from school, it's just special. I'm very lucky."
It's something McAvoy's parents talk about to each other, knowing that their son might never return to Long Beach.
They think that he has found another home, one that has welcomed him from the time he was 17 and a freshman in college, one that has seemed right for him since then, one that has made it easier to transition, to move up, to be the player that he -- and they and the Bruins -- believe he can be.
"I know that he loves Boston," Charlie McAvoy Sr. said. "I think we've lost him to the city of Boston."