BOSTON — After two scoreless overtimes, No. 8 UMass-Lowell put an end to the longest Hockey East semifinal game in history in the sixth stanza to beat defending national champions and No. 3 Providence 2-1 at the TD Garden Friday night.

It’s the sixth time overall that the River Hawks have advanced to the Hockey East finals and fourth consecutive appearance.

Hockey East playoffs

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In a one-penalty game, with the regulation goals both scored in the first period, the triple-overtime contest — and ninth-longest game in NCAA Division I men’s hockey, clocking in at four hours and 21 minutes — didn’t end without a bit of controversy.

The game-winning goal came at 12:27 into the what the players tabbed the last period of the “second game,” when Lowell senior co-captain A.J. White got a pass from teammate Michael Fallon, which hit off of his skate and went past Friars netminder Nick Ellis.

The goal went under a five-minute review to determine whether White used a distinct kicking motion to get it in.

“From what I remember, Fallon picked up a pass on the half wall there, he made a really good pass to me, I was trying to corral the puck and it kind of hit my skate and bounced toward the net — it might have even hit their D-man before it went in,” said White. “On a long review, you’re always a bit nervous, but I was just hoping it went our way.”

Providence coach Nate Leaman was unsure what to think of the call.

“Both goalies were the stars of the night, it’s just a shame the way it ended,” Leaman said. “I don’t want to question the referees; he was pretty adamant about calling it off right from the start. It’s just a gray area in our game. It’s really gray. I think half the coaches in our league would watch that play and say that’d definitely a kicking motion, the other half would say no way.”

It was a defensively driven game throughout for both teams. River Hawks goalie and Hockey East’s overall goaltending leader in GAA (1.62) and save percentage (.941) Kevin Boyle had 58 saves — the most ever by a Lowell goalie in the playoffs. Friars junior netminder Nick Ellis stopped 42 shots.

The Friars (27-6-4) got on the board first at 6:38 in the opening period when Brian Pinho took the puck down the left slot with a slap shot that rebounded off Boyle’s pads and directly to Nick Saracino. Saracino chipped it over to freshman Vincent Desharnais, whose wrist shot soared through the sea of red-and-blue Lowell jerseys, eventually up and over Boyle’s left shoulder for his first goal of the season.

With just over a minute left to go in the same stanza, the River Hawks (24-8-5) struck back to tie it up when sophomore C.J. Smith stick handled his way around a Friars defenseman and Ellis at the crease for his 17th goal of the season.

After four scoreless periods of back-and-forth momentum from both clubs, the fatigue set in among players by the end of the second overtime.

“We were just trying to stay hydrated,” said White. “And coach said if we stuck with the process, we would have a good outcome, so that was our mindset the whole time — staying positive and just sticking with what we knew and how we played.”

After a quick turnaround for some much-needed recovery and rest, the River Hawks will play in the championship game Saturday against either Boston College or Northeastern.

Lowell coach Norm Bazin put it simply: “We’re very excited to move on to the championship game. It was a good couple of games out there tonight.”