The runaway win helped break a three-way tie for third with Oklahoma, Kansas State and Iowa State all entering the day with 8-5 league marks. Iowa State's 71-60 Saturday win over TCU kept the Cyclones knotted with the Sooners.
Oklahoma (20-7, 9-5) dominated in nearly every category, leading by as many as 27 points in the second half.
The Sooners took their first lead 3 minutes in when Hield drained a 3-pointer following a Kansas State turnover. From there, Oklahoma outscored the Wildcats 34-17 to lead 41-22 at the half.
The Wildcats (18-9, 8-6) lost their sixth consecutive road game and are 1-6 in away league games.
Kansas State dug a hole early it couldn't climb out of, committing 10 first-half turnovers and shooting 39 percent with no starter scoring more than five points.
Oklahoma turned those turnovers into 17 points and controlled the tempo, outrebounding Kansas State 21-15 in the half and 32-28 for the game.
The Wildcats outscored Oklahoma 51-45 in the second half but it wasn't enough in what has been a difficult season away from home.
The Wildcats have done some of their best work this season at home inside Bramlage Coliseum -- winning their last 14 games, including beating No. 15 Texas and No. 7 Kansas.
Saturday's game was a much different story than when the two teams met in Manhattan, Kan., on Jan. 14. Kansas State led 39-38 after the first half and came from behind in the final 5 minutes to win 72-66 with five different players scoring in double figures.
Saturday, the Wildcats didn't have a player reach double-figure scoring until 7:51 remaining when Foster hit his second 3-pointer of the afternoon.
Both Oklahoma and Kansas State play two of their final three games at home.
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Leaving early for the NBA is a risky decision. Some players -- Skal Labissiere, Dejounte Murray -- slid in the draft. Some -- Isaiah Taylor, Troy Williams -- weren't drafted at all.
College basketball coaches across the country will hit the recruiting trail hard in July to target the Class of 2017's top prospects. Which players are the nation's top programs targeting?
The Tar Heels could lose Justin Jackson and Kennedy Meeks after next season. Coach Roy Williams has nearly every top-10 2017 prospect on his board.