After Kyler Kovich scored short-handed at 18:21 of the third period to bring Cornell into a 2-2 tie with Quinnipiac, Tim Rego won it for Cornell on a power play at 14:39 of overtime at Herb Brooks Arena in Lake Placid, N.Y.
Cornell will now play the winner of Dartmouth and Clarkson Saturday night for the ECAC Hockey playoff title and automatic bid to the NCAA tournament.
Jonathan Castagna opened the scoring for Cornell with a power-play goal at 19:56 of the first period.
Andon Cerbone tied it for Quinnipiac with a power-play goal of his own at 14:08 of the second before Chris Pelosi put the Bobcats up 2-1 at 14:42 of the third period.
Cornell goalie Ian Shane made 22 saves, while QU netminder Matej Marinov made 19 stops.
