Forward Brian Hart, shown here in previous action, was part of a talented freshman class that served as a much-needed bright spot for the Crimson this season. Hart and classmate Jimmy Vesey, the Ivy League Rookie of the Year, tied for third on the team with 18 points apiece while Kyle Criscuolo notched 11.

The Harvard men’s hockey team has run out of second chances.

The Crimson’s turbulent season came to an abrupt close Sunday as three unanswered Dartmouth goals in the second period helped the Big Green past the Crimson, 6-3, in Hanover, N.H.. After conceding game one to Harvard (10-19-3, 6-14-2 ECAC) on Friday, Dartmouth (15-12-5, 9-9-4) took the final two contests of the first-round series to advance to the ECAC Tournament quarterfinals.

“It’s frustrating for us because I felt that our guys really battled right to the end,” Crimson coach Ted Donato ’91 said. “We did a lot of good things…. We felt that the game was headed in our direction after the first period.”

Dartmouth will face Union in Schenectady, N.Y., for the next round of conference play on Friday. Meanwhile, Harvard will have to wait for next year. The Crimson, hampered by injuries and departures, struggled throughout the regular season and finished last in the ECAC for the first time in program history. But recent wins against Boston University and No. 1 Quinnipiac had signaled a possible late-season push.

“We were excited coming in,” Donato said after Sunday’s loss. “It’s no secret, a couple of the things we dealt with. I was proud of the way we finished the last three or four weeks of the season. But there’s no question that we didn’t end up where we would have liked to given where we thought we were headed at the beginning of the season.”

On Sunday, two goals less than a minute apart allowed the Big Green to jump out to a 3-1 lead early in the second frame.

Over six and a half minutes into the second period, Dartmouth freshman forward Tim O’Brien collected a deflected shot from teammate Mike Keenan and, uncontested, put the Big Green’s second goal past the right pad of a perplexed Raphael Girard, who was looking in the opposite direction in an attempt to locate the puck. Forty-nine seconds later, Eric Robinson batted a puck out of the air and between the pipes to give Dartmouth a 3-1 lead.

After the first period, the Crimson appeared to head into the locker room with game-changing momentum after a strike from senior forward Luke Greiner with less than 32 seconds left in the opening frame. But Dartmouth quickly caught fire in the second, drawing even 2:28 into the second period off a successful stuff attempt from freshman forward Brad Schierhorn.

The Big Green expanded on its lead early in the third as freshman forward Nick Bligh connected on a drop pass from classmate Connor Dempsey for a one-timer at the top of the right faceoff circle. Down 4-1, the Crimson pulled Girard in favor of freshman goaltender Peter Traber, who made his eighth career appearance in net.

“We lost sight of the puck there a couple of times early,” Donato said. “I think we made mistakes all the way up and down the ice. But at that point, I think we needed a change just as much for the rest of the team than really pointing the finger [at Girard].”

Harvard twice drew within two goals in the closing minutes as the Crimson outshot Dartmouth, 18-8, in the final frame. But each time, Dartmouth had an answer.

With less than 13 minutes left in regulation, senior forward Luke Greiner picked up a loose puck high in the Big Green slot to score his second goal of the game. Dartmouth senior forward Dustin Walsh responded seven minutes later, bouncing a puck off the back of Traber from behind the Harvard net to put the Big Green up, 5-2, with less than six minutes left in regulation.

In the closing minutes, freshman Crimson defenseman Desmond Bergin converted on a 6-on-4 opportunity after Harvard pulled Traber for an extra attacker on the power play. But with less than two minutes left, Schierhorn capped off a Dartmouth victory with an empty netter.

A 2-1 win on Friday put the Crimson on the brink of advancing to the ECAC Tournament quarterfinals for the fourth straight season. But for the second time in four years, the Crimson dropped the last two games of a series in Hanover to fall to a higher-ranked Dartmouth squad. Harvard lost game two and game three of the 2010 quarterfinals at Dartmouth.

Sunday was the final collegiate game for five Harvard seniors. Greiner finished the night with two goals and one assist while classmate and linemate Alex Fallstrom recorded his final NCAA point with an assist on Bergin’s goal. Captain Danny Biega, forward Marshall Everson, and defensemen Brendan Rempel also concluded their careers with the Crimson. Senior forward Connor Morrison was out of the lineup with an injury.

—Staff writer Michael D. Ledecky can be reached at mdledecky@college.harvard.edu. Follow him on Twitter @mdledecky.