Phil Forte scored 20 points -- seven of those during a decisive seven-minute stretch in the second half -- and Oklahoma State kicked off the Big 12 Conference schedule with a 61-47 victory over Kansas State on Saturday.
Le'Bryan Nash scored 11 points and had six rebounds for the Cowboys (11-2, 1-0 Big 12).
Thomas Gipson scored 14 points to lead Kansas State (7-7, 0-1), which lost its third straight contest.
Trailing 29-27 at halftime, Oklahoma State made a strong push early in the second half, going on a game-changing 25-4 run that included 15-straight points. The Cowboys built up a 54-37 lead after Jeff Newberry connected on a 3 from the left baseline with 11:16 to go.
The game hadn't seen more than a six-point lead before OSU's run.
During that dominating stretch, Anthony Hickey scored seven consecutive points for the Cowboys and Newberry also notched seven, including two free throws after he was knocked to the floor with a flagrant foul by K-State's Malek Harris with 15:51 remaining.
Kansas State went ahead 14-11 with 6:11 gone in the opening half when Nigel Johnson connected on a 3-pointer from the right baseline, but Oklahoma State reeled off a 12-3 run over the next four-plus minutes.
Back-to-back 3s from Forte, including one he lofted up from significant distance just as the shot clock expired, put the Cowboys up 23-17 with 9:42 left.
The Wildcats responded with eight consecutive points, retaking the lead at 25-23 when Justin Edwards slammed home a 2-on-1 pass from Wesley Iwundu as part of a 12-2 run. Kansas State led by two points at halftime.
Oklahoma State's Tavarius Shine scored eight points in a span of about two minutes early in the first half, with his 3-pointer from the left baseline with 12:29 left giving the Cowboys a 17-14 lead. The freshman from Irving, Texas did not score again, falling just short of his career-high 10 points on Nov. 28.
Kansas State's Marcus Foster entered the game leading the Wildcats with an average of 14.0 points per game, but was shut out on the day. Coming off the bench, he played just 14 minutes, shooting 0 for 4 from the field, including 0 for 2 from 3-point range.
Oklahoma State travels to No. 9 Iowa State on Tuesday.
Kansas State is at home to face TCU on Wednesday.