Boulder, Colo. ? Colorado’s high-scoring offense dictated the pace against No. 19 Oklahoma’s stifling defense to give the Buffaloes their first victory this season over a ranked opponent.

Richard Roby scored 28 points, and Chris Copeland added 18 for Colorado in the 84-75 victory Wednesday night.

The Buffaloes (17-5, 7-4) moved into a tie with the Sooners for third place in the Big 12 Conference and bolstered their argument that they deserve a spot in the NCAA Tournament.

They did it by outhustling the Sooners (16-6, 7-4) and shutting down Oklahoma’s inside combination of Taj Gray and Kevin Bookout.

Gray and Bookout finished with 11 and four points, respectively, both well below their season averages.

“We want to get into an up-and-down game, especially at home,” Roby said. “We felt that with the altitude, they wouldn’t be able to run. … With an up-and-down game, we felt we were able to eliminate their bigs.”

Michael Neal, who started in place of injured guard Austin Johnson, scored 26 points on 7-of-14 shooting from three-point range to lead Oklahoma. Johnson sprained his right ankle in Saturday’s 80-52 victory over Baylor and did not play.

Oklahoma guard David Godbold (15) fouls Colorado guard Marcus Hall in the Buffaloes' 84-75 victory. CU upended the Sooners on Wednesday in Boulder, Colo.

Terrell Everett added 18 points for the Sooners.

Nebraska 73, Iowa State 63

Ames, Iowa – Aleks Maric scored a career-high 37 points and grabbed 16 rebounds and Nebraska climbed back over .500 in Big 12 play. Jamel White added 13 for Nebraska (16-8, 6-5 Big 12), which snapped a two-game losing streak and won its second straight in Ames.

Maric, a center, ran roughshod over Iowa State’s interior defense – which has been its main weakness all season. He shot 13-of-15 from the floor, 11-of-15 from the free-throw line and scored 10 straight points late in the second half to help seal the victory.

Texas Tech 70, Kansas State 56

Lubbock, Texas – John Plefka scored 16 points to lead Texas Tech over Kansas State.

The Red Raiders led most of the way and took their largest lead, 63-36, when Dior Lowhorn hit a layup with 5:30 left in the game. Kansas State used a 15-2 run in the final three minutes to close within 70-56. The Wildcats hit three straight three-pointers, two by Lance Harris, and a bucket by Darren Kent with just 22 seconds remaining to close the gap.

Kansas State played sloppily much of the game, committing 17 turnovers.