AMES, Iowa -- Nicky Wieben scored 23 points and Iowa State closed the game with a 15-5 run to beat No. 21 Oklahoma State 63-55 on Saturday.
Amanda Nisleit added 12 points and 15 rebounds for the Cyclones, who rallied from an 11-point halftime deficit to snap Oklahoma State's 8-game winning streak.
Iowa State's Heather Ezell made a 3-pointer with 1:55 left to put the Cyclones ahead 53-50.
Ezell drew an intentional foul on her next shot, and Oklahoma State coach Kurt Budke was hit with a technical with 1:24 to go for arguing the call.
The Cyclones (13-2, 1-0 Big 12) hit eight free throws in the next 15 seconds, pushing their lead to 61-50.
Andrea Riley had 32 points to lead the Cowgirls (11-3, 0-1), including 20 in the first half to help put Oklahoma State ahead 32-21.
All 3 of Oklahoma State's losses have come on the road.