The NCAA men’s hockey tournament was whittled down to the final four teams last week, but some of most furious action occurred after teams were eliminated.

Within 48 hours of losing in the Northeast Regional, junior forwards Adam Gaudette of Northeastern and Jordan Greenway of Boston University had signed three-year, entry-level NHL contracts.

Greenway made his pro debut for the Minnesota Wild on March 27 in Nashville, Tennessee, with his college coach, David Quinn, in attendance. Gaudette arrived in Vancouver on March 26 after two flights totaling 10 hours and played his first game last Thursday against Edmonton.

The NCAA Tournament regionals are typically followed by a spate of college underclassmen signing with the NHL teams that drafted them. One day some players are fighting for a berth in the Frozen Four; the next they are pondering their professional futures.

“It’s just like flipping a switch,” Northeastern coach Jim Madigan said.

NHL teams pursue these players to fortify their rosters for the Stanley Cup playoffs, as the Wild did with Greenway, a second-round pick in the 2015 draft, or to prevent them from possibly becoming free agents following their senior seasons.

According to College Hockey, Inc., 10 players have gone to the NHL in recent weeks after the end of their college seasons. That includes Casey Mittelstadt, the eighth pick in the 2017 draft, who signed with the Buffalo Sabres last week after finishing his freshman season at Minnesota.

After losing to Ohio State in the Midwest Regional final on March 25, Denver lost its entire top line when Henrik Borgstrom, Dylan Gambrell and Troy Terry signed pro contracts. Terry, who like Greenway was on the U.S. team at the Olympics in February, played for the Anaheim Ducks on March 27 in Vancouver.

Denver coach Jim Montgomery, who played parts of six seasons in the NHL, called their signings “a foregone conclusion.”

“We have an open dialogue with our players, so we knew all were going to sign after this season,” he said.

North Dakota coach Brad Berry has seen 10 players leave early in the past three seasons, more than any other program.

The first college player to join the NHL this year was Harvard’s Ryan Donato, who, entering Tuesday, already had four goals in eight games for the first-place Boston Bruins. The Crimson were eliminated in the ECAC Tournament semifinals on March 16, and Donato skated for the Bruins three nights later — scoring a goal in a loss to Columbus.

Donato, Gaudette and Borgstrom are the finalists for the Hobey Baker Award, given to the best player in men’s college hockey.

Donato, who is still taking classes at Harvard, has the potential to have the kind of effect that Chris Kreider did for the New York Rangers in 2012. He joined the Rangers after winning a national championship with Boston College and scored five goals in the playoffs.

Quinn, the Boston University coach, saw sophomore Charlie McAvoy leave for the Bruins after the NCAA Tournament last year. He said Greenway had the opportunity to sign with the Wild after last season.

Typically, he said, he advises the player to think about his best interests before signing. “’What do you want? Are you ready to start your pro career? Are you ready for a year in the AHL?’” Quinn said. “They think one thing happens, and then the other thing happens.”

Berry, a former NHL defenseman, said players need a self-awareness of when the time is right to move on. “The bar is usually two years” in college, he said. “But players have different timelines.”

He noted that forward Drake Caggiula, now in his second year with Edmonton, did not blossom as a player until his senior year, in 2015-16, when he led North Dakota to the national title and was named most outstanding player of the NCAA Tournament.

“He needed all four years to get to where he wanted to go,” Berry said.

Craig Button, a former general manager of the Calgary Flames and currently TSN’s director of scouting, said college players are more advanced in their games and better prepared for pro hockey than ever before.

Still, he cautioned: “If you’re not ready, the league will chew you up and spit you out like you were nothing, no matter where you were drafted. The NHL is all about being ready. I believe players need more time, not less, in college.”

Madigan, the Northeastern coach, said going from the structure of a college environment to the NHL can be daunting.

“It’s almost like being a pro golfer,” he said. “You’re on your own.”

Before leaving for Vancouver, Gaudette, the top scorer in college hockey this season, wore his Northeastern gear for one last session on Matthews Arena ice, firing pucks into the net. He arrived in Vancouver with a Northeastern equipment bag.

“It still feels like it hasn’t set in yet,” he said to Canucks TV as he was being driven from the airport. “I’m not sure it will until I step on the ice for the first time. It’s just crazy how quick it all happened.”