Gostisbehere fired such a laser that it broke the stick of teammate Daniel Ciampini. The deflection bounced past BC goalie Thatcher Demko and Union had a lead it would not relinquish - even though BC sure tried.
"That doesn't happen that often," said Ciampini, who had his first career hat trick as Union held on for a heart-stopping 5-4 victory. "But when you've got a guy like that shooting the puck, it's bound to happen. That was a cannon."
Gostisbehere is the best defenseman in college hockey and, more importantly to those who bleed orange and black, property of the Flyers. A 2012 draft pick, Ghost had two assists and was a minus-2 on the night when he was often paired against Boston College's lethal top line.
"I saw him at the start of the year and he's come a long way," said Flyers assistant general manager Ron Hextall. "His game is a little more under control. We don't want him to be a rover. We want him to play real well defensively. He's improved a lot over the course of the year, but he does have some work to do."
Gostisbehere is a junior, so he still could decide to return to Union for his final season of eligibility. He offered no hint of whether he'd come out early, but there's not much more for the kid to gain at the collegiate level.
If he came out, he would be in the mix to make the Flyers out of training camp in September.
"I'm just worrying about [the championship game on] Saturday," he said. "I'm just taking this all in."
Union is ranked No. 1 in college hockey's latest poll, while Boston College is ranked third. The two teams put on a heavyweight bout that literally went down to the last second.
Ciampini, who also played a big role on that 5-minute penalty kill in the third, was the hero.
Each goaltender was peppered with shots and saw a ton of scoring chances, particularly in the last 8-plus minutes of the final period when Union and BC each scored twice.
Ciampini seemed to seal it with an empty-netter with 69 seconds remaining, but BC's Patrick Brown scored with 5 seconds left. Then teammate Johnny Gaudreau got off a reasonably good shot (considering the lack of time) from just inside the blueline that goalie Colin Stevens covered for save No. 34 and the Union victory.
"A couple more seconds would have been nice," Gaudreau said. "If we had 2, 3, 4 more seconds there, we could have had a nice play there."
Union will play for a national championship - in any sport - for the first time since the lacrosse team competed for a 1929 title. The Dutchmen have been competing at the Division I level in hockey since 1991-92.
"Just to see where our school has come from," Gostisbehere said. "I think it's been like 20-some years at Division I. It just says a lot where our program is."
Ciampini's broken stick is the neatest souvenir from the biggest goal in program history. At least until tomorrow.
"A young kid was asking for [the broken stick]," he laughed. "I had to say 'Sorry, buddy. This is going up on my wall.' "
If Gostisbehere is the best defenseman in the college game, Boston College's Johnny Gaudreau is its most dynamic forward. In fact, tonight he's expected to win the Hobey Baker Award as the best player in his sport.
Gaudreau scored the game's first goal, about 2 minutes in, and added a pair of assists. His game is similar to Danny Briere's.
Gaudreau was raised in Carneys Point, N.J., played at Gloucester Catholic and still has extensive roots in this area. His father, Guy, coach Briere's children in youth hockey.
Like Gostisbehere, Gaudreau is a junior. The Calgary Flames own his rights and the common thought is that he too will be a professional next year.
"I have to figure it out," he said. "Thankfully, I'm here with my family and in Philly. I'll be able to talk to all my family members about it."
Gaudreau said he'd like make a decision soon, and he's probably already made it. Though it's risky to try to gauge the body language of a 20-year-old, it sure seemed last night as though he's played his last college game.
Ciampini's hat trick was the first in the Frozen Four since Boston College's Nathan Gerbe in 2008 . . . Union coach Rick Bennett is 18-2 in the postseason, including 6-2 in the NCAA Tournament.
On Twitter: @EdBarkowitz