Boston University goalie Matt O'Connor gave up a tying own goal on a fluke play in the third period, then Brandon Tanev scored with 6:17 left and Providence beat the Terriers, 4-3, on Saturday night for its first NCAA hockey title.
It was the third consecutive year that the NCAA has crowned a first-time champion at the Frozen Four.
BU was seeking its sixth championship in a virtual home game when O'Connor easily gloved a puck that was lofted in by Kyle McKenzie from the red line. But he then lost track of the puck, dropping it and allowing it to fall underneath him. He slid backward to protect the net and wound up knocking it in with 8:36 to play.
Tanev scored off a faceoff to give the Friars the lead, and Jon Gillies helped protect it with a diving save against Nick Roberto in the final minutes. Gillies, selected the Most Outstanding Player of the Frozen Four, stopped 49 saves for PC (26-13-2).
Anthony Florentino and Mark Jankowski also scored for the Friars, who were the last school to be given an at-large berth in 16-team NCAA Tournament.
The PC fans who made the one-hour drive from the Rhode Island capital drowned out the sound of the final buzzer, and the players stormed over the boards to celebrate after the school's second trip to the Frozen Four, its first since 1985.
BU players skated slowly over to O'Connor to console him after the loss.
Ahti Oksanen and Danny O'Regan scored an NCAA Tournament-record 4 seconds apart for the Terriers (28-8-5) to overcome an early deficit, and Cason Hohmann gave BU a 3-2 lead in the second period. O'Connor stopped 39 shots.
But his gaffe cost BU the lead in a building where it had won so many times in the Beanpot and Hockey East tournaments — including both events this season. In all, the Terriers came into Saturday night with a 42-22-0 record at the TD Garden since it opened in 1995.
Oksanen tied it at 1 midway through the first period, then Hobey Baker Award winner Jack Eichel won the ensuing faceoff and skated into the Friars' zone before sliding the puck over to O'Regan for another goal. The previous record for fastest goals was 5 seconds apart, set by Michigan in the 1948 championship game against Dartmouth.
Jankowski made it 2-2 early in the second and Hohmann put BU back on top midway through the period. It stayed that way for 20 minutes as the game settled into a lull before O'Connor's mistake gave new energy to the Friars.
BU called a timeout with 6:19 left, and on the ensuing faceoff Tanev picked up the puck in the slot and wristed it in for the go-ahead goal.
Terriers coach David Quinn, in his second season since replacing longtime mentor Jack Parker, pulled O'Connor with 1:50 to play, and BU put sustained pressure on Gillies. The Terriers came closest to tying it when Roberto picked up a rebound with Gillies out of position, but the goalie dove back and got his arm onto the ice to stop the shot and protect the lead.
The Friars were the preseason favorite to win in Hockey East, they stumbled early and BU won the regular-season and conference tournament titles. PC won two games in the Providence regional to reach the Frozen Four, and then had another virtual home game against Nebraska-Omaha on Thursday to make it to the championship game.