An unexpected hero emerged for the Gophers on Saturday night.

Defender Olivia Knowles scored the game-winning goal at 3:05 of overtime as No. 2 Minnesota (18-2-1, 9-2-1-0) defeated Minnesota-Duluth (6-9-2, 4-6-2-2) 4-3 in the semifinal of the Minnesota Cup at Ridder Arena. It was Knowles’ third goal of the season.

Knowles received a pass from center Taylor Heise and flicked a wrist shot that went past Bulldogs goaltender Maddie Rooney. Rooney was screened on the play. Knowles’ teammates piled on top of her after securing a berth in the inaugural Minnesota Cup final.

“Any time you can win in overtime, it makes it special,” head coach Brad Frost said. “To score four goals on their goaltender is never easy to do. Credit Duluth, they dominated us at times. We haven’t been hemmed in our zone and had that many turnovers and bad [line] changes in a long time. That was disappointing, but in the end, we’re not going to apologize for winning.”

Knowles said she didn’t expect her shot to beat Rooney.

“I wouldn’t say it was a hard shot but the best thing about it was it was on net and it found its way to the back of it,” Knowles said. “I’m grateful it went in and thankful we [earned] the win.”

Minnesota-Duluth struck first 53 seconds into the game. The Bulldogs went on a two-on-one rush. Center Gabbie Hughes fed left winger Anna Klein the puck. Klein fired a one-timer past Gophers goaltender Alex Gulstene. It was Klein’s fifth goal of the season.

Minnesota answered at the 11:44 mark of the first period. After Rooney denied center Amy Potomak on a breakaway, left winger Taylor Williamson followed up and deposited the rebound to tie the game at one.

Williamson gave Minnesota a 2-1 lead at 6:15 of the second period. Like her first goal, she beat Rooney on a rebound after Rooney stopped a shot from right winger Alex Woken. It was Williamson’s eighth goal of the season and second of the game.

Williamson said she sensed when Potomak and Woken would give her opportunities to capitalize.

“Being without the puck and breaking down the ice with them, I knew they were going to have the ability to get it on net,” Williamson said. “I was busting as hard as I could. It happened to end up on my stick.”

The Bulldogs tied the game 25 seconds into the third period with a power-play goal. Hughes beat Gulstene with a wrist shot after Gophers defender Patti Marshall attempted to pass the puck to Knowles. It was Hughes’ eighth goal of the season.

At 8:50 of the third period, right winger Grace Zumwinkle scored her 14th goal of the season, beating Rooney with a hard slap shot from just outside the faceoff circle. Minnesota fans at Ridder Arena hoped Zumwinkle’s goal would hold up as the game-winner, but Minnesota-Duluth right winger Sydney Brodt had other ideas.

Brodt beat Gulstene with a wrist shot at 14:55 of the third period. Her goal sent the game to overtime.

Minnesota-Duluth had multiple chances to win the game in overtime, but Gulstene made three saves before Knowles ended the game for the Gophers. Gulstene stopped 33 of 36 Duluth shots to win her 14th game of the season.

Gulstene said Minnesota-Duluth came out hard in the first period and helped her regain her form.

“After break, I was ready to go,” Gulstene said. “Practice all week was great. It felt awesome, especially to come off a win like that.”

Minnesota will face St. Cloud State (7-15-2, 2-12-1-1) in Sunday’s Minnesota Cup final at Ridder Arena. The opening faceoff will be at 4:07 p.m.

Frost said Minnesota needs to be more crisp with passes and have better line changes in the final.

“Our turnovers were horrendous and our line changes were bad, but we found a way,” he said. “We have a chance to raise a trophy and win a tournament tomorrow, which we’re excited about.”