LAWRENCE, Kan. (AP) — Kansas guard Elijah Johnson had a chance to tie the game. All he needed to do was take another dribble, pull up at the 3-point line and hit an open jumper.
Instead, the senior turned it over.
The No. 2 Jayhawks were forced to watch helplessly as Phil Forte went the other direction for a layup at the buzzer that only served to punctuate Oklahoma State's 85-80 victory Saturday.
The loss snapped Kansas' nation-leading 18-game win streak and a 33-game run of success at Allen Fieldhouse.
"All he had to do was shoot it," Kansas coach Bill Self said of Johnson's turnover with a few seconds left. "He crossed over and I don't know where he was going, and he lost it."
Lost a whole lot more than just the ball, too.
Kansas had not lost at home to Oklahoma State since 1989, and its home winning streak was tied for the fourth-longest in school history. Coming in, Self had lost only seven times at the Phog in 164 games.
"This one hurts, definitely," said Jeff Withey, whose three blocked shots moved him into second place in program history. "We don't really lose at home."
Ben McLemore had 23 points to lead the Jayhawks (19-2, 5-1 Big 12), who rallied from a 14-point first-half deficit. Kevin Young added 12 points and Withey finished with 10.
Markel Brown scored 28 points and Marcus Smart had 25 for the Cowboys.
"We just beat one of the top teams in the country, and a great team at that," said Brown, who celebrated with a cart-wheel and back flip. "It's hard for teams to come into their home court and get a victory. We're one of the few teams that have done it. We couldn't believe it."
Smart had a pair of key put-backs in the closing minutes, helping the Cowboys (15-5, 5-3 Big 12) go on a 13-2 run that turned a 66-62 deficit into a 73-68 lead with just over a minute left.
The Jayhawks managed to play savvy defense and take advantage of a couple missed free throws, trimming the Cowboys' lead to 81-80 on a layup by Elijah Johnson with 18.8 seconds left.
But Forte, an 89-percent foul shooter, made both of his tries with 7.9 seconds to go, and Johnson turned the ball over before Kansas could try a tying 3-pointer.
"We were definitely a better team with him sitting down over there next to us watching the game," Self said of his senior guard, who was a key part of last year's national runner-up.
Johnson's turnover in the closing seconds was the 16th of the game for the sloppy Jayhawks. They also had 16 earlier in the week, when they struggled to get past West Virginia.
"We don't have a guard," Self said despondently. "We don't have a point guard."
Having one sure would have helped in the first half.
That's when the Cowboys took control with a 19-3 run, taking advantage of the Jayhawks' lousy offense while getting the ball in the hands of Brown, who had 11 points during the surge.
"We had to come out, punch them in the mouth and not let the crowd get into it," Brown said.
By the time Brown was fouled by Johnson and converted the three-point play with 10:58 left in the half, Oklahoma State had a 26-12 lead — the largest by anybody on the Jayhawks all season.
Kansas eventually went on an 11-3 run of its own to get back into the game, but Brown delivered another 3-pointer out of a timeout and Oklahoma State managed to maintain a 40-34 lead at the break.
Brown finished the first half with 22 points, just two off his season high. The junior guard was 7 of 10 from the field, 5 of 7 from the arc and even had a couple assists.
Brown hit another 3 out of halftime before Kansas finally started to execute.
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 game, 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."