Maria Cordero added 15 points, Shaunte Smith had 14 points and a career-high 17 rebounds and Danielle Green scored 13 for OSU (21-4, 9-3 Big 12).
After Cordero's 3-pointer gave the Cowgirls a 57-42 lead, Earnesia Williams answered with a layup to start a 15-4 run by the Longhorns. Her 3-pointer got Texas within 61-57.
Carla Cortijo hit another 3-pointer with 9.5 seconds left to cut the deficit to 69-66, but Riley hit her final two free throws to provide the final margin.
Ashley Lindsey had 18 points and 10 rebounds to lead Texas (16-10, 4-8). Cortijo added 15 points, Brittainey Raven scored 12 and Williams had 11.
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