EAST LANSING, Mich. (AP) -- Michigan State switched to a 2-3 zone defense, and suddenly No. 4 Penn State couldn't score.

	Penn State's Marissa Graby, right, sneaks a pass past Michigan State's Jennifer Callier.

The Lady Lions went 8:04 without a basket in the second half as Michigan State scored 16 unanswered points en route to a 71-63 victory Sunday.

"If I had to go back to a key time in the game, that was it," Penn State coach Rene Portland said. "They went to a 2-3 zone, and it gave us a little trouble. We didn't attack, and that was one of the things we wanted to do."

With a stifling defense, Michigan State held the Lady Lions to 25 points on 24.2 percent shooting in the second half.

"We did the best I've ever seen a team do on defense and on the boards," Michigan State coach Karen Langeland said. "I can't say enough about our defensive play in the second half."

The win came against the highest-ranked opponent the Spartans (14-4, 5-2 Big Ten) have ever beaten while they extended a home unbeaten streak to 12 games. For Penn State (16-3, 7-1), the game snapped a 12-game winning streak.

"Obviously we're disappointed," Portland said. "I commend Michigan State. They wanted it a little more and played a little harder, but we're going to learn from this."

Andrea Garner scored 12 of her 14 points in the first half as Penn State opened a 38-35 halftime lead. The Lady Lions went ahead 42-37 on a basket by Maren Walseth at 18:35 left. But Michigan State took control with a 16-0 run, opening a 53-42 lead with 11:27 left to play.

Michigan State's post play continued to pace the team as Becky Cummings scored 18 points and Kristen Rasmussen used 13 second-half points to finish with 17 points and 11 rebounds.

"All of our post players did a great job on their big people," Rasmussen said.

The Spartans outrebounded the Lady Lions 26-18 in the second half and 46-35 overall.

"They didn't have one of their best games," Langeland said. "But I'd like to think that we had something to do with that."

Sparked by 10 first-half points by Cummings, the Spartans managed 26 of their first 30 points from the post.

"We came up big, and if there was ever a team effort this was it," Langeland said.

Maria Recker added 13 points for Michigan State. Garner grabbed 13 rebounds for Penn State, Walseth scored 17 points and Chrissy Falcone had 11.