Led by 32 points from Keita Bates-Diop, Ohio State stunned top-ranked Michigan State, 80-64, in Columbus.
The Buckeyes ended the first half on a 12-0 run and never looked back.
C.J. Jackson added 14 points for OSU, which improved to 13-and-4 overall and 4-and-0 in the Big Ten.
They host Maryland on Thursday.