Ben McLemore, on pace to replace Danny Manning as the highest-scoring freshman in Kansas history, misfired on his first eight shots before making three in a row in the second half. He had a season-low seven points.
Smart started out 0 for 9 before finally hitting a fallaway jumper along the right side of the lane to cut Oklahoma State's deficit to 53-51 with 3:20 left in regulation. Forte tied it soon after, making a pair of free throws after coming up with a steal.
Smart came out of the game once after hurting his right shoulder and again after tweaking his right ankle in the first half. He then got socked in the face by Withey early in the second half. But it wasn't until he got his fifth foul that he finally couldn't return.
Elijah Johnson missed a pair of free throws with the chance to put Kansas up by five in the first overtime, only to have Brown return the favor on the Cowboys' end. But Johnson fouled out in the scramble for the rebound, and Brown then made both his attempts to draw Oklahoma State within 61-60 with 2:35 remaining.
After two free throws by Releford, Oklahoma State's Forte drilled a 3-pointer from the left corner with 56.4 seconds left to tie it at 63. The game went to a second overtime after McLemore air-balled a 3-pointer, Smart came up empty on a drive and Releford missed a driving attempt for Kansas. Smart's desperation shot from three-quarters court grazed the front of the rim.
The Jayhawks weren't able to close it out in regulation after Releford banked in a tricky scoop shot underneath for a 57-53 lead with 1:49 to play. Smart made one of two free throws at the opposite end and, after Withey missed inside for Kansas, he got out in transition for a 3-pointer to tie it with 1:11 to play.