John Clay rushed for 104 yards and scored a pair of touchdowns and the Badgers turned back a fourth-quarter challenge to hang on and send the nation's No. 1 team down to a defeat.
Wisconsin (6-1, 2-1 Big Ten) blunted the Buckeyes' comeback attempt when James White scored on a 12-yard run. It was the first time Wisconsin has defeated a top-ranked team since 1981 when they beat Michigan.
Scott Tolzien went 13-of-16 passing for 152 yards and was intercepted once for Wisconsin.
Ohio State (6-1, 2-1) saw its 12-game winning streak snapped. The Buckeyes got a pair of rushing touchdowns from Dan Herron and Terrelle Pryor compiled a 14-of-28 passing mark for 156 yards.
But he was picked off late in the fourth by Blake Sorensen to thwart a drive.
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