Ostrow scored his second goal of the game and 10th of the season following a turnover deep in the Duluth zone at 13:40 as he beat the Bulldogs goalie McNeely high on the stick side to start the flurry and get the Pioneers to within 3-2.
Knowlton followed 36 seconds later with a tally of his own following assists by Daniel Doremus (Aspen, Colo.) and Zajac at 14:16. The goal marked Knowlton's team-leading 12th this season and his first since Dec. 29 vs. Boston University and knotted the score at 3-3.
Zajac sealed the comeback and capped the furious rally with a power-play goal at 15:11 of the third to give the Pioneers their first lead at 4-3 and seal the series sweep.
The turning point of the game for Denver came just prior to the scoring outburst as the Pioneers completely shifted momentum by killing a total of 5:30 in penalties. For the game, Denver received 31 penalty minutes from the officials, while Minnesota Duluth was tagged with just 14.
The victory improves Denver's record to 15-8-4 overall and 10-6-4 in the conference loop. The win also assured the Pioneers of their first conference sweep since Nov. 16-17 vs. Colorado College and its first road league sweep since Nov. 9-10 at Minnesota State. Minnesota Duluth slips to 10-13-3 with the loss and 8-9-3 in league action.
The Pioneers now sit in a tie for third place with Minnesota and North Dakota in the WCHA standings each with 24 points.
Minnesota Duluth (10-13-3, 8-9-3 WCHA) got on the scoreboard first, taking only 65 seconds to claim a 1-0 advantage as sophomore Caleb Herbert snuck a shot past Denver goaltender Juho Olkinuora (Helsinki, Finland) on a wrist shot just inside the left circle.
The Bulldogs kept the pressure on in the Denver zone as it totaled 15 shots in the frame, but Olkinuora was up to the task for the Pioneers as he made 14 saves in the opening 20 minutes.
Freshman Austin Farley put away another quick strike for the Bulldogs at the beginning of the second period, which they opened with 1:42 remaining on a power play, as he scored his 11th goal of the season after fellow freshman Tony Cameranesi slid a cross ice pass and found Farley just outside the crease for a one-timer, to make the score 2-0.
Denver (15-8-4, 10-6-4 WCHA) trimmed the margin to 2-1 on a goal by Ostrow, his ninth of the season and first since Jan. 12, following assists by sophomores Ty Loney (Valencia, Pa.) and Josiah Didier (Littleton, Colo.) at the 8:13 mark of the second. Ostrow beat Duluth goalie Matt McNeely with a shot from just right of the crease.
Minnesota Duluth reclaimed the two-goal advantage at 16:19 of the second after it capitalized on a power play for the second time in the contest. Cameranesi buried a slapper from the front of the left circle following a nifty setup by Mike Seidel to make the margin 3-1.
Denver won despite being out-shot for the game 33-24. The Pioneers finished the game 1-for-3 on power play opportunities, while Duluth capitalized on 2-of-7 chances.
Olkinuora finished with 30 saves while earning his second straight win and ninth of the season. Minnesota Duluth goalie McNeely turned away 20 shots in the loss.
Denver won the the overall faceoff battle 47-29. Ostrow led the Pioneers on the draws capturing 19-of-26.
Denver will return home for the first game of a two-game series vs. intra-state rival Colorado College in the resumption of the Gold Pan Series. The Pioneers and Tigers will square off on Friday at Magness Arena in a 7:37 p.m. (MT) start that will be broadcast live on ROOT Sports and Denver's 102.3 FM ESPN Radio.
Visit DenverPioneers.com for complete coverage of all 17 of DU's NCAA Division I sports.
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