KANSAS CITY, Mo. — The postseason hopes of three Big 12 schools all but vaporized Wednesday at the Sprint Center, as Oklahoma, Colorado and Iowa State all felt the sting of defeat in what will likely be the last game of each school’s season. 12th-seeded Nebraska pulled the upset of the day, hitting better than 50 percent from the field to top the ice-cold Missouri Tigers.

Texas Tech defeated the Buffaloes to advance to a second round matchup with Kansas at 11 a.m. today.

NEBRASKA 75, MISSOURI 60

Nebraska’s Brandon Richardson finished with 19 points, including a key second-half four-point play, to lead 12th-seeded Nebraska in a 75-60 upset against 5-seed Missouri.

Richardson was one of four Cornhuskers to finish the game in double figures, as Nebraska, which entered the game with just two conference victories to its name, shot a staggering 55.8 percent from the field to pull off what will likely be the upset of the tournament.

On the flipside, Missouri shot an atrocious 33.9 percent, and though the Tigers are still a solid bet for the NCAA tournament, this defeat will drop their seeding significantly.

“These guys have done a tremendous job,” Missouri coach Mike Anderson said. “When people counted them out, they were picked seventh in the league, and they finished fifth, one game out of second place. So with that being said, I think we’ve done what we are supposed to do.”

With Nebraska so hot from the floor and the Tigers struggling to hit shots, senior guard J.T. Tiller said it seemed like the deck was stacked against them at times.

“Today seemed like it was Murphy’s law: What could go wrong would go wrong,” he said. “Everything they were putting up there — I see it as it was their day, and they really wanted this game. And it really showed in the results.”

Nebraska will move on to face Texas A&M, which is coming off of a first-round bye, at 2 p.m. today. The winner of that game will play the winner of Kansas-Texas Tech in the semifinals.

TEXAS TECH 82, COLORADO 67

The Colorado Buffaloes got yet another outstanding performance from Big 12 Freshman of the Year Alec Burks, but it wasn’t enough to hold off Texas Tech’s domineering team effort.

Burks led all scorers with 24 points on 8-of-14 shooting, but the Red Raiders had four scorers in double figures — highlighted by John Roberson’s 19-point, nine-assist performance — and controlled the boards in an 82-67 Texas Tech victory.

“He passed the ball well, hit key shots,” Texas Tech coach Pat Knight said of Roberson. “He was talking again. He’s out there trying to calm guys down. He was talking in the timeout.”

Knight and the Red Raiders move on to face the No. 1 seed, and the No. 1 team in the country, Kansas, at 11:30 a.m. today. Knight and his players know the challenge that awaits them — they were manhandled when they visited the Jayhawks in January, losing 89-63 in Allen Fieldhouse.

“It’s going to be tough,” Knight said. “It’s like comparing my win-loss record with my old man’s.”

Knight’s old man is Bobby Knight, a 902-game winner as a head coach and one of the greatest to ever roam the sidelines in college basketball. Head coach Pat Knight just won game No. 31.

Tech’s leading scorer, Mike Singletary, was held scoreless in Lawrence, but he averages just under 15 per contest for the Red Raiders.

“It’s always fun to play Kansas,” Singletary said. “It’s always fun to play the so-called best team in the country. So I’m going to take that as a challenge. I think we’re all just going to take it as a challenge and just go out there and play with the same energy we played with today and just, hopefully, we’ll come out with a win.”

OKLAHOMA STATE 81, OKLAHOMA 67

Oklahoma State reeled off a 20-2 run in the first seven minutes of the game and Oklahoma never pulled back within single digits. The Cowboys won in an 81-67 thumping that was never even as close as the final score.

Diminutive point guard Keiton Page scored 19 points in the first half as the Cowboys put the game out of reach before the second TV timeout.

The Cowboys built an 18-point halftime lead despite a relative off night from conference player of the year James Anderson. Anderson had just six points at the half and finished with 11.

“We take a lot of pride in our defense,” Oklahoma State coach Travis Ford said. “We spend more time in practice on defense, but when you make shots like that, it makes everything else look so much better.”

Anderson’s final basket came on a highlight-reel dunk over Oklahoma’s Tommy Mason-Griffin. Oklahoma was without leading scorer Willie Warren, but Mason-Griffin and Steven Pledger combined for 40 points. It wasn’t enough for the Sooners, whose Achilles-heel defense proved to be their undoing once more as the Cowboys shot well over 50 percent from the field.

Oklahoma State moves on to face Kansas State at 6 p.m. today. The Cowboys defeated the Wildcats in Manhattan in the game following Kansas State’s upset of then-No. 1 Texas.

“I don’t want to say the first game’s always the toughest because now we’ve got Kansas State,” Ford said. “That’s not the case, but it’s good to get the first one out of the way.”

TEXAS 82, IOWA STATE 75

Before the game, senior forward Damion James told his team the seniors were only guaranteed two more games. But he wasn’t ready to go home Wednesday.

James led all scorers with 28 points and 16 rebounds while leading Texas to an 82-75 victory against Iowa State.

With every other Big 12 game of the day being decided by 14 or 15 points, this was the most competitive game of the day. Despite the seven-point victory, Texas still dominated Iowa State.

Iowa State was down 9-2 to start the game but came alive with an alley-oop from junior guard Diante Garrett to junior forward LaRon Dendy. Then sophomore guard Scott Christopherson tied the game 9-9 with a three-point basket on the ensuing possession.

The crowd was heavily populated with Cyclones fans and those two plays made them come alive. But the Longhorns still went into halftime up 31-28.

The Longhorns, mainly James, responded to every comeback the Cyclones tried. James took over offensively and defensively in the second half, whether it was a steal, dunk or crucial rebound.

“He was a man on the boards,” Texas coach Rick Barnes said. “He just went and got everything.”

In what is most likely Craig Brackins’ last college game, the junior guard scored 15 points and had six rebounds, but it wasn’t enough for the Cyclones.

Iowa State fought off an eight-point deficit with just under nine minutes to go. They were still down 59-60, but the Cyclone faithful was on its feet. But James was there to knock down a three and put them back in their seats.

“When you’re doing that, you’re having fun,” James said.

The Longhorns went on an 11-0 run to help close out the ball game. The Cyclones didn’t get within six points in the second half. Texas will play Baylor at 8:30 tonight.

— Edited by Jess Rangel