DeBerdine created the winning play after stealing the ball and taking it back toward the goal for the score. With the win, Maryland (10-1, 3-0 B1G) picked up its third win in extra time this season, all over top 10 opponents.
"The quality of this match was outstanding," head coach Missy Meharg said. "The outcome was the right outcome with the quality of what we played. We couldn't be more pleased. We hit cross bar, the post more than once. We can always take better shots. We'll continue to work on that and I have confidence they'll fall."
Senior Kelee Lepage opened the scoring when she collected a pass near the top of the circle, brought it in a few steps and scored just inside the right post. She gave Maryland a 1-0 lead just 5:08 into the match. It was her first goal of the year.
The Terrapins held on to their one-goal lead for over 50 minutes and didn't allow the Wildcats (10-3, 3-1) a shot for the first 34 minutes of the game.
Northwestern tied the match with just 2:21 to go when Kirsten Mansfield tied it up.
In the 7-vs.-7, golden goal overtime periods, Maryland took four shots to the Wildcats' two before DeBerdine's goal.
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Just 5:34 into the second overtime period, DeBerdine intercepted the ball and carried it back towards the goal, where she took a shot from the right side and rattled it in across the cage.
The Terps finished with 20 shots to the Wildcats' five. The Maryland defense held Northwestern's Bente Baekers, the nation's leading scorer, to just two shots on the day. Senior goalkeeper Noelle Frost made two saves.
Next, the Terps will return home to host No. 3 Connecticut (9-1) at the Field Hockey & Lacrosse Complex Sunday at noon. Admission and parking are both free for Sunday's game.
DEFLECTIONS: Maryland owns the all-time series over Northwestern, 18-8… Since joining the Big Ten in 2014, the Terps are 49-8 in conference play… Maryland is 3-0 in overtime or shootout games this year and 70-25 overall… Meharg is 575-139-9 (.802) in her 32 years as head coach.