BOSTON – For a third year in a row, the Div. 1 boys hockey state final at TD Garden saw the game-winning goal scored in the final minute of regulation.

But for the first time in 16 years, the ultimate trophy is back in the hands of the state’s winningest hockey program.

Senior Tommy Hurst concluded his first year on varsity by scoring the game-winner with 21.3 seconds left, propelling No. 4 Catholic Memorial (19-6-1) to a 4-3 win over No. 14 St. John’s of Shrewsbury on Sunday for the program’s state-leading 18th championship.

Fellow senior Luke Long had just tied the score less than four minutes earlier, anchoring a comeback win to stop the Pioneers (12-13) just short in a true thriller.

“It means a lot,” said Catholic Memorial head coach Larry Rooney. “I put my heart and soul into this. I work at CM, two of my boys went to CM. We’ve had our disappointing games where we believed we were one of the top teams in the state. To win a game like this means a lot to me.”

“It feels awesome,” Long added. “Growing up, I said it before and I’ll say it always, CM’s always been the school to go to, with their history. Feels great to finally get (the school) back here. … It’s just a really proud feeling, all the people that wore the jerseys before us.”

Belief has been a major theme for both program’s all tournament, leading to quick responses as part of four different lead changes.

St. John’s entered the third without a deficit for the first time over the last three rounds, and frequent hero Daniel Menyalkin connected with Caleb Keyes to take the Pioneers’ first lead, 3-2, with 8:11 left in regulation.

Catholic Memorial dialed up the offensive intensity, and after nearly four minutes of near misses or Colin McCarthy saves (28), Long’s shot tipped off McCarthy’s glove to make it 3-3.

“We were working them the whole shift there,” Long said. “Tons of shots, good opportunities. Threw it on net and it happened to go in.”

Menyalkin nearly took the lead again for St. John’s with under two minutes left, but eighth-grade goalie Jaxson Fleming (18 saves) stopped the Grade-A bid.

Teams limited opportunities from there, but junior James Baker sent a pass from outside the right dot to sophomore Christian Hinckle (goal, assist) at the doorstep, and he deflected it to Hurst in the slot for the game-winner.

“Unbelievable feeling,” Hurst said. “Still speechless from it. It’s all God’s doing, honestly. … I’m blessed to have this opportunity.”

It was fitting for both of the crucial goals to come from seniors, who have guided a mostly young group throughout the title run.

“Senior leadership was fantastic,” Rooney said. “When you have that young team, you need older guys like Seamus Tattan, and Luke Long, and Cam Reed, and Tommy Hurst, and Morgan Lenehan, and Lincoln Hennessy to lead those young guys, and they did.”

Catholic Memorial scored first on a goal from Hinckle with 1:50 left in the first period. Teams traded goals within a two-minute, 17-second scoring spree early in the second, as St. John’s junior Tyler Bergman, Catholic Memorial senior Cam Reed, and St. John’s sophomore Ryder Bisson each scored in a 2-2 tie.

Once St. John’s led, there wasn’t any panic for the Knights.

“There was always believability that we were good enough,” Rooney said. “And I saw that believability probably way back in January. … So when you get into situations like that, you’re down by a goal late in the game, the believability just came out.”