Oladipo also provided seven rebounds and six steals for the Hoosiers (18-2, 6-1 Big Ten).
Christian Watford (12 points, six rebounds) and Kevin Ferrell (11 points) also reached double figures for Indiana in the victory.
The Spartans (17-4, 6-2), meanwhile, saw their six-game winning streak broken despite 21 points from Gary Harris.
Adreian Payne chipped in with 18 and nine rebounds in the loss.
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