LAWRENCE, Kan. (AP) -- Kendall Smith scored 24 points, including the clinching free throws in the final seconds, and Oklahoma State held on to beat seventh-ranked Kansas 84-79 on Saturday.
Cameron McGriff added 20 points and Jeffrey Carroll had 15 for the Cowboys (14-9, 4-6 Big 12), who built an 18-point first-half lead and dominated the boards in ending their three-game losing streak.
It was the third loss for the Jayhawks (18-5, 7-3) in Allen Fieldhouse, their most since the 1998-99 season, and their second in conference play. They also lost to Texas Tech in the Phog.
Devonte Graham gave them a chance when his two foul shots with 14.2 seconds left drew Kansas within 82-79. But after squandering several seconds trying to foul Smith, the guard capped his big performance off the bench by knocking down two free throws to put the game away.
Udoka Azubuike had 20 points and Graham and Svi Mykhailiuk scored 17 apiece for Kansas, which was celebrating 120 years of basketball by welcoming back dozens of former players and coaches.
They didn't have much to cheer about on a sunny Saturday morning.
A nip-and-tuck start gave way to complete first-half dominance by the Cowboys, who at one point had more second-chance points (18) than the Jayhawks had total (16).
One of the nation's most prolific 3-point shooting teams, the Jayhawks were relegated to dumping the ball to Azubuike in the post. And the big fella was unable to keep up with Oklahoma State's own 3-point barrage, which at one point stretched the lead to 18 points late in the half.
Kansas coach Bill Self, who typically stalks up and down the sideline, instead sat glumly in his seat as his team followed a 3-for-15 start from the field with three consecutive turnovers.
The Jayhawks' 46-33 halftime deficit matched their biggest of the season.
They dug into their disadvantage early in the second half, quickly trimming the lead to seven points on Newman's flurry of baskets. But for the next 10 minutes, the Cowboys matched Kansas shot-for-shot, answering each attempt at starting a run with a crucial rebound or big basket.
The Cowboys still clung to a 78-71 lead after Newman missed a foul shot with about 2 minutes left, and Smith scored twice as the Jayhawks were trying to foul him to keep a comfortable lead.
Kansas finally got the game to one possession, only for Smith to hit the clinching foul shots.
120 YEARS OF HOOPS
The Jayhawks recognized the birth of its basketball program during a halftime ceremony, highlighted by the 30th anniversary of their 1988 title team. There was also a reunion banquet on Saturday night with more than 400 players, staff and coaches from every era expected to attend.
Oklahoma State had a 41-28 advantage on the glass, which produced a 26-7 advantage in second-chance points. That kind of hustle not only infuriated Self but proved to be too much for Kansas to overcome.
Kansas was coming off a dominant performance at Kansas State, but its shooting went wayward as the Cowboys mixed up zone and man-to-man defenses. The Jayhawks were just 8 of 22 from beyond the 3-point arc with several of their makes coming down the stretch.
Oklahoma State returns home against Baylor on Tuesday night.
Kansas continues its homestand Tuesday night against TCU.