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.