10th-ranked Iowa’s leading scorers on the season were at their best, especially Clark. The 6-4 guard scored 28 points, handed out 15 assist and grabbed 10 rebounds for her Big Ten record eighth career triple-double.
She frequently set up Czinano, who scored almost at will around the basket and finished with 22 points on 11-for-13 shooting.
Mikesell gave Ohio State a 24-23 lead with a last-second 3-pointer to end the first quarter, but Iowa dominated the second stanza to open up a 43-34 halftime lead.
After a quiet first quarter, Clark had seven points in the second, but perhaps more importantly she set up four more baskets for teammates, including a quarter-ending layup by Czinano that gave the Hawkeyes their largest lead to that point.
Czinano had 14 points in the first half and made 7 of 9 shots.
McMahon led Ohio State with 11 points in the first half, but she was only 4 for 12 from the field.
Still playing without star point guards Lacy Sheldon and Madison Greene, Ohio State struggled to create good shots in the first half and made only 14 of 36 from the floor, including 2 of 12 three-pointers.
Greene is out for the season after tearing an ACL, but Shelton is expected to return at some point from a lower leg injury.
Iowa extended to a 10-point lead when Sydney Affolter scored following an offensive rebound with 6:41 left in the third.
She put back her own miss less than a minute later to make it a 12-point game and cause Ohio State head coach Kevin McGuff to call a timeout with 5:52 on the clock.
The Hawkeyes did not score again in the third quarter as McMahon ignited a 10-0 run with a mid-court steal and a feed to Ebony Walker for a layup.
McMahon had the last basket of the run when she put back her own miss with a minute left, but she missed a layup that could have cut the deficit to one.
In a battle of long-time Big Ten heavyweights, the Hawkeyes may have been saved by the bell.
The sellout crowd at Value City Arena was rocking during the third quarter, but Iowa scored eight of the first 11 points in the fourth quarter to regain control.
They led by as many as 13 down the stretch as the Ohio State offense continued to struggle.
Defensive rebounds were also a problem for the Buckeyes, who allowed Iowa to collect 13 of its misses and convert those to 15 points.
Aside from McMahon, Taylor Thierry also had a standout night for Ohio State, scoring 20 points on 7-for-16 shooting. She added nine rebounds and three assists in 33 minutes.
Indiana also had one loss entering the night. The Hoosiers were set to play at Michigan later Monday night and host Ohio State on Thursday night.