KANSAS CITY, Mo. — Bill Self had a decision to make, his Kansas basketball team’s hopes of extending its Big 12 Tournament run beyond just a single day at stake.

Needing a frontcourt option midway through the first half of Thursday afternoon’s quarterfinal contest against Oklahoma State, here were Self's options: go back to Silvio De Sousa, who three months ago was in high school, or give an extended look to James Sosinski, a walk-on who three months ago was a full-time KU football player.

The hall of famer sought a second opinion on the admittedly surreal situation.

“I thought Silvio was bad early, so I told our guys, ‘Let’s put James in before Silvio’ the second time,” Self recalled. “And they’re like, ‘No.’ So I’m probably glad I made that decision.”

Indeed.

Self pushed all the right buttons in the absence of starting center Udoka Azubuike, and the depth-challenged Jayhawks defeated the Cowboys for the first time this season, 82-68, to advance to a 6 p.m. Friday semifinal against in-state rival Kansas State at Sprint Center. Malik Newman scored a career-high 30 points on 11-for-15 shooting, but more on that later — the biggest storyline coming out of this contest was the performances of De Sousa and Mitch Lightfoot, pressed into bigger roles as Azubuike sits this tournament out with a sprained medial collateral ligament in his left knee.

Lightfoot, the 6-8 sophomore forward, drew the start in Azubuike’s absence and finished with eight points and six rebounds in 23 minutes, also drawing a pair of key charges in the second half. De Sousa, the 6-9 freshman forward who joined the team in late December from IMG Academy in Bradenton, Fla., scored six points and hauled in eight boards, including seven rebounds in a first half which saw the Jayhawks (25-7) claw back from a 10-point deficit to take a one-point lead, 43-42, into the break.

For Self, the bigs’ performance was a mix bag of sorts, though one he would've taken in a heartbeat entering the contest.

“They did fine,” Self said. “They got 14 (points) and 14 (rebounds), so statistically before the game I probably would’ve said we’d sell out for that. How many balls were in our hands? How many times did we commit a dumb foul on 3-point shooters late game? A lot of things probably wouldn’t allow them to grade out great, but certainly their production helped us win the game. They did a nice job.”

Relief may be the most apt word to describe the postgame locker room for the Jayhawks, who avoided losing their third game this season to the eighth-seeded Cowboys (19-14). De Sousa, sporting a big grin, filmed the horde of media streaming into the locker room, most gathering around Big 12 player of the year Devonte’ Graham.

“Oh, you know, we’ve got a big-time player of the year, so I’ve got to record him,” De Sousa said, “just to keep on my phone for his birthday next time.”

Lightfoot, meanwhile, said he thought the KU bigs played pretty well, but “I still made a lot of stupid mistakes,” he admitted. He lauded De Sousa’s “sponge”-like ability to absorb advice, adding he’s “proud” of the player that has become a protégé of sorts. Lightfoot also recalled the uneasy feeling when Azubuike suffered his injury in the final 10 minutes of the team's practice Tuesday in Lawrence.

“Obviously it sucks. I think we all know that,” Lightfoot said. “It’s just next man up. That’s always been our theory. This team has done a great job of taking adversity and using it for good and playing harder because of it.”

Graham, who finished with 10 points and nine assists, echoed that comment from Lightfoot. He said he believes the team plays better with its back against the wall and its depth in doubt, citing an earlier victory over Kentucky in the team’s second game of the season. KU learned just hours before that contest that freshman forward Billy Preston would be withheld indefinitely, but the group rallied for a 65-61 victory.

“Everybody is expecting you to lose or to have an excuse if you lose — ‘Oh, you didn’t have Azubuike, you should’ve lost,’ but nah, we don’t think like that,” Graham said. “It’s always next man up. We’ve got to rally together, support one another and go out and get the job done.”

No player rallied the Jayhawks more than Newman, who scored 20 of his career-best point total in a dynamic first-half showing.

OSU took its 10-point advantage, 24-14, on a 3-pointer by Jeffrey Carroll, a shot which capped runs of 12-0 and 16-2 for the Cowboys. Carroll did a celebratory spin in front of the KU bench after the make, and he had every reason to — at the time, OSU was shooting 62.5 percent from the field and had made 4 of 5 attempts from beyond the arc, including three from Carroll. The Cowboys, playing for their postseason lives, entered the game 223rd nationally in field-goal percentage (43.8 percent).

But OSU went ice-cold offensively from there, going 1 for 17 from 3-point range the rest of the way, and Newman caught fire.

Newman's back-to-back treys gave KU a 33-30 advantage with 6:13 left in the opening period, and a De Sousa dunk on a Graham lob made the advantage five and capped runs of 8-0 and 13-2 for the Jayhawks. Svi Mykhailiuk’s short put-back jumper at the buzzer gave KU its one-point halftime lead, and the Jayhawks led the rest of the way, powered by a 14-0 stretch midway through the second half that coincided with a nearly eight-minute scoring drought for the Cowboys.

Newman kick-started the rally with a 3-pointer and a pair of free-throw makes. KU finished 8 of 20 from 3-point range, with the sophomore guard contributing four of those makes.

“Malik putting us on his back was huge,” Self said. “To be down 10 early when they just kicked us last week and they were making everything it seems like and we’re struggling, to have him put us on his back and get us to halftime with a one-point lead ... that was big for us. Going forward, without Udoka especially, we’re going to have to have some perimeter player play great, maybe two to play great to give us the best chance.”

Back to the bigs, and where KU goes from here.

Self said it’s too small a sample size to say life will be just fine without Azubuike, the NCAA’s leader in field-goal percentage at 77.4 percent. While the 7-footer is “feeling better,” as Self put it, a return for the Jayhawks’ first weekend of NCAA Tournament play may still be an optimistic stance. Makol Mawien, who scored 16 points on 6-for-7 shooting and grabbed nine rebounds in K-State's 66-64 overtime victory over TCU on Thursday, will be a load to handle inside Friday.

But for at least one game, the Jayhawks proved something, at least to themselves.

“I would say we just showed that we can play without Udoka, and we can win,” Mykhailiuk said. “He is a force for us and he can score whenever he wants to, but right now he can’t play and it’s a little bit (of a) different team. We drove a lot more and we shot a little bit more 3s. ... We play a little bit faster and I would say a little bit more scrappy on defense, but it just changed us a little bit.”

That change had to be evident to Graham, who, in the final minute of the first half, shared the court with Sosinski. Asked what his response would’ve been three months ago had someone told him he’d be directing an offense at times featuring a then-high schooler and a walk-on from the football team, Graham chuckled and smiled.

“We might be in trouble,” Graham said of his likely response at the time. “But you know, we doing a good job. Everybody’s adjusting. When your number is called, you’ve just got to step up and play your role and know what it is you’ve got to do to win.”