Max Novak had a goal and an assist and top-seeded Union beat Providence 3-1 on Saturday to win the NCAA East Region championship and advance to the Frozen Four for the second time in three years.
Mat Bodie and Matt Hatch also scored for Union (30-6-4), which is unbeaten in its last 15 games, and had won its last 10.
The Dutchmen, who lost in the 2012 national semifinals to Ferris State, are ranked No. 1 in the nation for the first time in program history.
Nick Saracino scored with a little more than 5 minutes left in the third-period for Providence (22-11-6), which trailed 2-0 after two.
But the Dutchmen ended the Friars' comeback hopes 1:08 later when Novak went behind the net and found Hatch in front for a one-timer.
"We knew we wanted to find the soft spots in the slot," Hatch said. "That was part of our game plan, and I just kind of got lost and Max made a great pass out."
Union opened the scoring just 2:42 into the game on a slap shot from Bodie, who took a cross-ice pass from Daniel Carr at the top of the left circle and found top right corner of the net.
Union's Colin Stevens had 25 saves, including a key one in the first period when he managed to glove a rebound shot from point-blank range by Derek Army.
He also was helped by Hobey Baker finalist Shayne Gostisbehere, who jumped into the net when Stevens got out of position and made a flurry of saves that preserved the 1-0 lead.
"That was a massive play in the game," Bodie said. "I thought it was a goal. But you need those breaks sometimes in these types of tournaments."
Union scored again 58 seconds into the second period.
Novak, who was named the region's most outstanding player, put a backhand shot on net that seemed to be stopped by
Providence goalie Jon Gillies, who had 28 saves. But the puck kept moving underneath him and slowly trickled into the net as Hatch poked at it. Novak, who scored twice in Friday's win over Vermont, got credit for the score.
Stevens came up big again in the second stopping a shot by Steven McParland after the Providence wing stole the puck and skated to the front of the net.
Providence pressed the attack in the third, outshooting Union 12-9, and breaking through when Saracino found a rebound to the right of the net put the puck over Colin Stevens' glove.
"We knew we had to be desperate in the third, our season was on the line," Saracino said.
This was the first game between Union and Providence since coach Nate Leaman left the Dutchmen to take over the Friars after the 2011 season.
Rick Bennett, his former assistant, has led the Dutchmen to the regional finals in each of the last three seasons. Bennett was a former Hobey Baker finalist when he starred at Providence and is a member of the Friars' Hall of Fame.
"I just want to let (coach Leaman) know that a part of him is a part of this team too," Bennett said.
The Friars had not been to the NCAA tournament since 2001 and hadn't not won a game since 1991.