Mike O'Leary's power-play goal 2½ minutes into the third period gave No. 16 Notre Dame a 1-0 victory over visiting Michigan State on Friday in the opener of the Big Ten best-of-three quarterfinal series.

It was O'Leary's sixth goal of the season for the Irish (19-13-3), the No. 2 seed in the conference playoffs.

Cale Morris made 27 saves for the shutout. John Lethemon made 23 stops for the Spartans (12-18-5).

Wisconsin 4, No. 18 Penn State 3: Sean Dhooghe's third goal of the game, with 1:50 left, enabled the visiting Badgers (14-16-5) to defeat the Nittany Lions (19-14-2) in Game 1 of their playoff series. Dhooghe also scored late in the first period and in the middle of the second. He has 15 goals this season. Tarek Baker recorded the other goal for Wisconsin. Daniel Lebedeff had 37 saves for the Badgers. Penn State goaltender Peyton Jones stopped 38 shots.

WCHA quarterfinals

Lake Superior State 4, Bemidji State 2: Anthony Nellis' power-play goal midway through the third period gave the Lakers (22-11-2) a 3-1 lead, and they held on to beat the visiting Beavers (15-16-6). Nick Cardelli and Brad Johnson scored Bemidji State's goals.

No. 4 MSU Mankato 3, Alabama Huntsville 1: Marc Michaelis scored two power-play goals, early in the second and third periods, to lead the host Mavericks (28-7-2) over the Chargers (8-27-2).

NCHC

No. 1 St. Cloud State 4, No. 3 Minnesota Duluth 3 (OT): Nick Perbix' second power-play goal of the game, at 3:16 of the extra period, gave the Huskies (26-4-3, 18-2-3-1-1 NCHC) the victory over the visiting Bulldogs. The game was tied 2-all after the first period and neither team scored in the second. Perbix's first goal put SCSU ahead 3-2 just under five minutes into the third period. Riley Tufte of UMD (21-10-2, 14-8-1) tied the score at 3-all at 9:28.

No. 19 North Dakota 2, Nebraska Omaha 1: Colton Poolman scored 2:53 into the third period and the host Fighting Hawks (17-15-2, 11-11-1 NCHC) beat the Mavericks (9-21-3, 5-16-2). Gabe Bast also scored for North Dakota, which got 23 saves from Peter Thome.