BUFFALO, N.Y. — For a while, it seemed like typical UMass.

When Denver forward Cole Guttman beat Filip Lindberg five-hole to bring the Pioneers back from a two-goal deficit late in the third period of Thursday’s Frozen Four matchup, the Massachusetts hockey team looked done.

The Minutemen spent the entire third period of the national semifinal sitting back and absorbing pressure, trying to get through the final 20 minutes without squandering their 3-1 lead, but squander the lead they did. UMass had already lost two players to game misconducts, and Denver had all the momentum in the world.

But with their backs against the wall and the season on the line, the Minutemen delivered.

Freshman Marc Del Gaizo ripped a one-timer past Filip Larsson 15:18 into overtime, and that old UMass story was no more.

“This team, all year long they’ve impressed everybody,” said UMass coach Greg Carvel. “Tonight was just the next chapter of how resilient they are. I thought in overtime, we were down, we lost two players, two forwards, playing three lines. We went deep into that overtime period. We played three lines for almost two periods, and the kids dug deep, once again, proved the resiliency, proved the culture that we have on our team is our strength and carries us, and it did again tonight.”

Adversity hit early, as UMass captain Niko Hildenbrand was hit with a game misconduct and a five-minute major just 6:24 into the first period, and two minutes later the Pioneers opened the scoring.

The Minutemen roared back with three goals in under two minutes to go to the locker room with a 3-1 lead — it seemed like UMass had seen adversity and handled it, but the Minutemen had plenty more coming.

Already down their captain, the Minutemen took another big hit when leading goal-scorer Mitchell Chaffee was tossed in the same fashion as Hildenbrand, and suddenly UMass had lost two forwards with a full period left to play.

But UMass still had a lead — until Cole Guttman beat Lindberg blocker side to cut the lead to one with nine minutes remaining, before shoveling one five-hole to erase the deficit with under four minutes to play.

The Minutemen had blown a two-goal lead in the biggest game of their lives; they were tired, undermanned and shell shocked. But they weren’t done yet.

“We’re a young team,” Del Gaizo said, “but we learned. Just like we learned in Boston, we’ve been learning all year. I don’t think there was any panic really on the bench. We regrouped and got back together for the overtime.”

UMass came out a bit sluggish in the overtime period, as playing with 11 forwards started to wear on the Minutemen. But there were bright spots, as Mario Ferraro, Oliver Chau, Bobby Trivigno and Brett Boeing put in some strong shifts in overtime.

“I’d say a guy that definitely stepped up today was Mario,” said defenseman Cale Makar. “He’s just an energy guy. He gets the boys going. I don’t know if you guys seen the video that UMass posted on Twitter, he’s pretty energetic. No, we have a lot of guys on this team that can bring the energy. We just have to keep it high.”

Denver had all the momentum going into sudden death, but through a few quality chances — and a handful of saves from Lindberg — the Minutemen started to swing things.

Chau and Trivigno especially created chances down low in the final minutes, but Larsson wouldn’t budge in the Pioneer net. With 5:47 left in overtime, Carvel used his timeout to give his tired team a minute to settle.

“We had some guys caught on the ice there,” Del Gaizo said. “It was a smart move calling a timeout there. Look, the whole way in overtime, we were plugging along. As far as like regrouping, I don’t think it was that much of a regroup. I think it was just guys [were] tired. It was effective, so it was a good move.”

It took all of 65 seconds for the breather to pay off, as Chau found Del Gaizo for the one-timer, and the freshman defenseman fired a tired, shorthanded UMass team into the national championship game.

“Exactly what [Del Gaizo] said, nobody’s panicking,” Makar said. “Everybody in the room was calm. We knew when we got the opportunity on the ice, we’d put one in. Fortunately [Del Gaizo] did for us.”

It wasn’t easy — it never is — but Carvel had faith in his guys, and his guys came through.

“For some reason in overtime, I just, I felt fine,” Carvel said. “That’s coming off a third period where obviously we were outplayed and they had the momentum. I went into the locker room as soon as we came off the ice, and you know the body language, and the hanging and the mopiness — I said, fellas, done. Change. One goal, next goal wins. I’ll give them credit. They came out, that’s as resilient as you can be, to give up a two-goal lead late in the game.

“So for them to come out, I thought Denver, second and third [periods] was the better team, we were better in the first, then we were better in the overtime. That’s a hell of a sign. This team again, they’ve done things all year long that have impressed people, impressed me. I guess at some point I think tonight in overtime I just felt they were going to find a way, and they did.”

A blown lead, a tired team, two key cogs sitting in the dressing room — none of it mattered. UMass saw adversity and faced it, and the Minutemen are marching on.

Amin Touri can be reached at [email protected], and followed on Twitter @Amin_Touri.