Marble connected on 7-of-13 shots from the floor and grabbed six rebounds for the Hawkeyes (14-3, 3-1 Big Ten), who bested a ranked foe for the first time this season after earlier losses to Villanova and Iowa State.
Melsahn Basabe had a double-double of 11 points and 10 rebounds as Iowa knocked off its first Top 5 opponent since 2001.
Mike Gesell also netted 11 points.
The Buckeyes (15-2, 2-2) dropped a second straight despite 22 points and seven rebounds from LaQuinton Ross.
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