According to College Hockey, Inc., 10 players have gone to the N.H.L. 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 United States 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 N.H.L., 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.
Last year the sophomore forward Brock Boeser, Vancouver’s first-round draft pick in 2015, played for the Canucks in Minnesota two days after the Fighting Hawks were eliminated in double overtime by Boston University in the first round of the N.C.A.A. tournament. This year Boeser was the leading rookie goal scorer with 29 goals until a back injury ended his season on March 5.
“That’s college hockey now,” Berry said. “You try to get high-end players and develop them.”
The first college player to join the N.H.L. 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 E.C.A.C. 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 impact that Chris Kreider did for the Rangers in 2012. He joined the Rangers after winning a national championship with Boston College and scored five goals in the playoffs.
Quinn, the B.U. coach, saw the sophomore Charlie McAvoy leave for the Bruins after the N.C.A.A. 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 A.H.L.?’” Quinn said. “They think one thing happens, and then the other thing happens.”
Berry, a former N.H.L. 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 time lines.”
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 N.C.A.A. 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 were 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 N.H.L. 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 N.H.L. 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.”