MANCHESTER, New Hampshire — At this point in the season, it’s fair to say a few things about this No. 2 Boston University men’s hockey team — it doesn’t play well early in games, but it comes on strong late.

We’ve seen this played out many times over the course of the year, and Friday’s NCAA Northeast Regional opener was much the same. Sloppy play marred the Terriers through the first period and a half, but a strong third period put them right back in the game.

Like many times before, the process mattered little compared to the end result. And that’s something BU won’t be complaining about.

On the strength of two third-period goals and junior forward Danny O’Regan’s rebound tally at 7:21 into overtime, the Terriers (26-7-5) defeated No. 17 Yale University 3-2 and moved on in the NCAA Tournament. BU now sits just one win away from the Frozen Four.

“What a hockey game,” said BU head coach David Quinn. “I’d like to congratulate Yale on a great season. It’s no mystery why they’re in this tournament. They play as hard as anyone we play against, they’ve got a great goalie. It really was everything that we thought it would be. We knew it would probably come down to a one-goal game — possibility of overtime.”

By the time O’Regan tapped in the winning goal, both teams had missed plenty of chances in overtime. Even with a wide-open net, the junior winger wasn’t taking anything for granted.

“The way the game was going I thought I could’ve put it over the net, maybe,” O’Regan said. “I definitely had a bunch of chances early and the goalie kind of had my number, I think I caught a post. That net was pretty gaping and I got a lucky bounce for once so it was a nice open net for me.”

Bounces like that, though, at least through the first two periods, almost exclusively went in favor of Yale (18-10-5). Only missed shots and a red metal pipe kept the game scoreless through one period.

Early in the first, Yale winger Frankie DiChiara stole the puck in the BU zone, skated in all alone, but hit the crossbar on a backhander. The Bulldogs had at least three other prime opportunities off BU turnovers, though none hit the net. The mistakes would eventually catch up to the Terriers, as Yale converted about halfway into the second period on a power-play tally from defenseman Nate Repensky.

Quinn admitted most of the early-game issues came from a tentative and young defensive group that may have been nervous under the bright lights of the NCAA tournament.

“For the most part, early in the game,” Quinn said, “I thought our defense were backing off quite a bit, they weren’t involved in the offense.”

But being down a goal going into the third period is not a new situation for BU. In fact, the Terriers thrive during times like that. They had the Bulldogs right where they wanted them.

BU’s offense started generating good shots at the end of the second period, but goaltender Alex Lyon stopped the first 19 shots he faced. The Terriers kept up the attack in the third, and eventually it paid off.

Junior winger Ahti Oksanen, whose elbowing penalty earlier cost the Terriers a goal, made up for it with a score of his own. At 8:21 in the third, the junior cleaned up a rebound and deposited it past Lyon for his 24th goal of the year. Not long after, the Terriers broke through with their first lead of the game.

Senior captain Evan Rodrigues fired a shot from the left circle, and the puck slid past Lyon low glove side at 11:20 of the period.

“I thought in the last three or four minutes, we did a good job in the second period, then in the third period, I thought we did all the things we needed to do,” Quinn said. “I thought we did the things we did against Merrimack [College] and [University of Massachusetts] Lowell and we got rewarded for it.”

The Terriers did just about everything right to have a chance at winning the game in the third period, outshooting Yale 14-2 in the 20 minutes. However, one of those shots got past junior goaltender Matt O’Connor.

DiChiara, twice denied on great chances, this time scored to tie things up. He took a feed in the center of the slot and wrsited it high over O’Connor’s blocker with less than seven minutes to go in the period.

With time winding down in the third and BU on the power play, O’Regan was positioned perfectly in front of the net for a rebound and nearly won the game. But his shot rang off the crossbar, and the game went to overtime.

Almost in the same exact position 7:21 later, O’Regan would have a better result.

He potted in a rebound ofg freshman center Jack Eichel’s initial shot, giving the Terriers the win. It was O’Regan’s second overtime-winning goal this season, which have both been set up by his linemates, Eichel and Rodrigues.

“I play with two really skilled players who know how to create chances,” O’Regan said. “They usually get a lot of pucks to the net, so it’s not a bad place to go. I usually get a few bounces every game and sometimes capitalize on them. Yeah, that one I guess was just a combination of, coach was harping on it, just get to the net and good things will happen.

“I was able to catch a lucky bounce.”