Morgan Paige scored a career-high 33 points to lead Wisconsin to a 63-61 upset over seventh-ranked Penn State on Thursday night.
Tiera Stephens scored the game-winner on a putback with 5 seconds left to end the Nittany Lions' 12-game winning streak.
Stephens scored five points and had 11 rebounds and Jacki Gulczynski added 16 for Wisconsin (10-11, 2-6 Big Ten). The victory against a ranked opponent was the Badgers' first since a 48-45 win against Michigan State on January 14, 2010.
Maggie Lucas scored 18 points and Mia Nickson added 11 for Penn State (17-3, 7-1).
The Badgers came into the game having lost seven of their last eight games.
The Lady Lions routed the Badgers 84-40 at home two weeks ago for their most lopsided victory since 2001.