The Spartans (17-3, 6-1 Big Ten) won their sixth straight game with the help of Branden Dawson, who provided a double-double of 18 points and 13 rebounds.
The Badgers (13-6, 4-2), meanwhile, got 10 points and seven rebounds from Mike Bruesewitz but couldn't avoid their second consecutive defeat.
Jared Berggren added nine points and nine boards for Wisconsin.
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