McLemore led the way with 11 points during a 16-4, momentum-changing run. Twice he finished off alley-oops from Johnson, and his lay-in with 13:23 left gave Kansas a 50-47 lead.
Smart and Brown refused to let the Cowboys wilt, though.
Smart, who considered Kansas before signing with the Cowboys, scored back-to-back baskets, and Forte finally scored after missing his first eight field-goal attempts. Brown then hit his seventh 3-pointer, pulling Oklahoma State within 59-58 with just over 8 minutes left in the game.
Forte added his first 3 moments later, and Michael Cobbins followed up a miss by Forte with a massive dunk that allowed the Cowboys to regain a 67-66 lead with 3:45 remaining.
"They got the best of us, definitely, on offensive rebounds," Withey said.
Le'Bryan Nash, who had struggled all gam, beat the shot clock with a jumper with 2:40 left that gave Oklahoma State a 69-68 lead. And despite some tense moments down the stretch, they did enough on defense and at the foul line to hang on for a signature victory.
"It's a big win, winning at Kansas. That's one of the biggest wins of our season right now," Nash said. "It was a good win, but we still want more."
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