Kansas forward K.J. Adams Jr. (24) celebrates after an and-one bucket against Oklahoma State during the second half on Saturday, Dec. 31, 2022 at Allen Fieldhouse.

Oklahoma State coach Mike Boynton has been around basketball long enough to know that a 15-point lead at halftime, like the one he had over No. 4 Kansas at Allen Fieldhouse, is never an indication that the game is over.

Add the fact that Boynton’s Cowboys on Saturday were playing a team that has a pretty impressive recent history of big comebacks, and the lead suddenly feels even less secure.

As it turned out, it wasn’t safe at all, as fourth-ranked Kansas turned a 45-30 halftime deficit into a thrilling, 69-67 victory.

Kansas outscored the Cowboys 39-22 and turned it over just one time in the second half to bring home the program’s 32nd consecutive win in a Big 12 opener.

“It was the exact same thing as the national championship game,” Kansas coach Bill Self said after the win, referencing KU’s 40-25 halftime deficit against North Carolina last April. “You turn up, you tie it earlier than you could ever anticipate and then it becomes a basketball game. Because you can’t sustain that over 20 minutes. And then, when it became a basketball game, it was kind of like a heavyweight fight. Fortunately, we got the last blow.

“The second half, that’s about as turned-up, good, solid man-to-man defense as we’ve played in a long time,” Self added. “They got five points in the first 12 minutes and (both baskets) were off offensive rebounds. I mean, we were turned up.”

The Cowboys (8-5 overall, 0-1 Big 12) dominated the first half of play, taking advantage of some hot shooting and a sluggish Kansas effort on both ends of the floor.

The Jayhawks (12-1, 1-0) dodged a couple of moments where it looked like OSU might go up by 20. One came after Kansas guard Bobby Pettiford hit the floor to try to save a turnover but was out-hustled to it by OSU’s Chris Harris Jr., who flipped it to Moussa Cisse, who quickly passed it to Caleb Asberry for a 3-pointer that put Oklahoma State up 29-21 with 4:30 to play in the half.

A few minutes later, KU’s Jalen Wilson took a pass on the wing, but started his drive before he caught it. The ball slipped through his hands and led to an OSU fastbreak and three-point play on the other end that put the Cowboys up 42-27 late in the half.

Those types of moments plagued KU throughout the first 20 minutes. The halftime break gave them a chance to regroup, but the Jayhawks did more than that. They reenergized.

But the change in intensity did not come from any sort of epic halftime yelling by Self. Instead, Kansas took more of an analytical approach to getting back into the game.

“I didn’t get on them at halftime,” Self said. “We said, ‘Well, we screwed that up; what are we going to do now?’ That was just them. Jalen needed to lead.”

That he did. Wilson finished the day with 20 points — 10 in each half — but it was his message to his team, a few short words and a reminder that they could get it done, that sparked the comeback.

“Just stay calm,” Wilson said of the focus at halftime. “We’ve been there plenty of times before. There aren’t any 15-point plays. The main thing was to just win every 4 minutes and that’s what we were able to do. … Fifteen points may seem like a lot, but in a 20-minute span it’s not.”

Putting it that way makes it sound routine. KU’s second-half comeback was anything but.

For four straight possessions to open the half, Kansas’ defensive intensity was so ramped up that OSU either turned it over or didn’t get a shot off. That brought the fans to life, and the combination of KU’s newfound fire on the floor and the wall of sound smacking the Oklahoma State players in the face was enough to lead to another great Kansas comeback.

“Give Kansas credit for their fight,” Boynton said. “We played a pretty good first half and really disrupted what they were doing. And then they flipped the aggressiveness and it obviously turned the tide.”

First came a 5-0 run that immediately cut the OSU lead to 10. Dajuan Harris Jr. hit a 3-pointer and Gradey Dick a jumper to make it 48-38, OSU.

Then, after a 3-pointer by former Jayhawk Bryce Thompson pushed the OSU lead back to 13 (48-35), Kansas scored 17 of the next 19 points, the final three coming on a 3-pointer by Wilson, to give the Jayhawks a 52-50 lead with 10:56 remaining.

In all, the Kansas run went to 25-7 during the first 12:02 of the second half.

While Boynton gave credit to Kansas for its comeback, Self was sure to point out that the Cowboys deserved some credit, too. Not many teams can take a punch like that from the defending national champs and still stay in the game until the final seconds, but that’s exactly what OSU did.

The final 6:20 of Saturday’s game featured five lead changes, with three different Jayhawks putting KU ahead — Joe Yesufu, Kevin McCullar Jr. and KJ Adams — and Thompson hitting two clutch 3-pointers to either tie or put the Cowboys up late.

The first came off of a play called in a timeout, as Thompson shook McCullar by running him into a screen and Dick simultaneously. The second came after Wilson’s free throws put Kansas up 67-64 with 23 seconds to play.

With the clock winding down, Thompson drilled his seventh triple of the day from the left wing to tie the game with 14 seconds remaining. Rather than calling timeout, KU quickly pushed the ball up the floor and got it to their point guard. Harris delivered his ninth assist to Adams on a perfectly timed roll to the rim.

Adams did the rest, finishing in tight like he did late in KU’s win over Duke, and Kansas got two stops on the other end to close out the victory.

“I didn’t want us to settle for any jumpers,” Wilson said of the late sequence. “Especially with the momentum that we had. They had a guard down there (on Adams) so that was the perfect play and he just had to make the shot.”

Of the game winner, Adams said: “It’s easy to play when you don’t have that much pressure on you. When you’re Kevin or J-Wil, you have a lot of pressure on you, but I’m kind of playing over there with a free mind.”

Adams made all six shots he took in Saturday’s win and hit two of three tries at the free throw line.

After a few seconds expired as OSU brought the ball up the floor, Oklahoma State’s last-ditch effort actually worked. Despite not having used the late out-of-bounds play in a game this season, Boynton drew it up in the timeout with around six seconds to play and it led to Thompson coming through the lane unchecked with nothing but the basket in front of him.

McCullar recovered in time to block the shot out of bounds from behind. And the Cowboys’ final prayer, with 0.3 seconds on the clock, was tipped by KU big man Ernest Udeh Jr., before it could get anywhere near the rim.

Every bit of the second half was reminiscent of some of the most memorable games in recent KU memory. Self and Wilson referenced the national title game. But it also called to mind the 16-point halftime deficit at Kansas State last season and a 19-point deficit at home to Missouri in 2012. In all of those games, Kansas had to be ultra-energized and nearly perfect to get the job done, and they did.

Now they can add Saturday’s win to that list.

“We’ve been there before,” Wilson said.

Added Self: “That was a tough game. That took every bit of energy we had.”

Saturday’s win was the 300th for Self inside Allen Fieldhouse. He is now 300-16 in 20 seasons at KU’s home venue.