LAWRENCE, Kan. -- Kansas spent most of the first half Monday night chasing Iowa State all over the court, unable to keep up with the Cyclones' crisp ball movement and their resulting open shots.
Jayhawks coach Bill Self made a subtle tweak that changed everything.
Kansas began switching five on defense, and the stops fueled a 14-0 second-half charge that gave Self's team the lead. And unlike last weekend at West Virginia, the ninth-ranked Jayhawks made it stick down the stretch, holding on for an 80-76 victory over the No. 24 Cyclones.
"We buckled down," the Jayhawks' Devon Dotson said. "We really wanted to get that win."
Dedric Lawson led the way for Kansas (16-3, 5-2 Big 12) with 29 points and 15 rebounds. Marcus Garrett added 16 points, Lagerald Vick had 14 and Dotson finished with 10, including the clinching free throws with 5.9 seconds left that effectively put the game away.
"They move the ball so well," Garrett said, "and it went from corner to corner and we couldn't guard it. Then we made the switch and we were able to contain."
Iowa State (14-5, 4-3) still got within 72-71 on a driving layup by Marial Shayok with 1:44 to go, but Garrett followed a swap of empty possessions with a layup. Michael Jacobson hit a free throw for the Cyclones, but Lawson's 3 from the top of the key made it 77-72 with 22.3 seconds left.
Shayok added the last of his team-high 26 points for Iowa State, and after Dotson made the second of two free throws, Tyrese Haliburton made two of his own to get within 78-76 with 7.5 seconds left.
Dotson was immediately fouled on the inbound and this time he made both of his free throws.
It allowed the Jayhawks to escape with a split of the season series after getting blown out at Hilton Coliseum earlier this month. It also kept Kansas from falling a game behind the Cyclones in what has already become a jammed race for the Big 12 championship.
"I thought the biggest adjustment they made was just the physicality they defended us with," Cyclones coach Steve Prohm said. "That's on me. This one is on me."
Talen Horten-Tucker finished with 16 for the Cyclones. Jacobson had 10 points and 11 rebounds.
The Cyclones took the lead in the opening minutes of the first half and never really relinquished it, even though the Jayhawks kept making brief runs that threatened to push them ahead.
Iowa State maintained control with crisp passing, balanced offense and enough rebounding, while the Jayhawks relied heavily on Lawson, who had 15 points and eight boards at the break.
The fact that Kansas was always a possession or two from taking the lead ramped up the nervous energy inside Allen Fieldhouse, turning it into a powder keg. And it finally erupted when Lagerald Vick slammed an ally-oop in transition to give the Jayhawks a 55-53 lead with 10:23 to go.
Lindell Wigginton and Horten-Tucker had chances to stop the run, but they combined to miss three straight foul shots. It eventually reached 14-0 when K.J. Lawson scored on a scooping layup, giving the Jayhawks a 61-53 advantage with 8 1/2 minutes left in the game.
Foul trouble soon became a problem for both teams.
Ochai Agbaji, who provided a big lift off the bench in the first half, fouled out for Kansas on a loose ball with 6:32 to go. Horten-Tucker soon picked up his fourth, and the Cyclones' Cameron Lard was on the floor for about a minute before fouling out with no points and two rebounds.
Kansas still led 69-62 when Wigginton knocked down a 3-pointer. Jacobson added a free throw, then made a spectacular defensive play before hitting a 3 of his own to knot the game 69-all.
From there, it call came down to the final couple minutes.
Four members of the Jayhawks' 2008 national championship team were seated behind the Kansas bench in an impromptu reunion: Sasha Kaun, Mario Chalmers, Sherron Collins and Brandon Rush. All of them but Kaun have their names hanging in the rafters of the Phog.
Iowa State's hot shooting staked the Cyclones to an early lead, but a series of timeouts by Prohm did little to slow down the Jayhawks during their big second-half run. And when Iowa State had chances to stop it at the foul line, a series of misses cost dearly.
Kansas improved to 14-2 at Allen Fieldhouse under Self, and is now 38-3 since the 2013-14 season when coming off a loss. The Jayhawks also avoided falling to 4-3 to start Big 12 play for the first time since the 2004-05 season.
Iowa State visits Mississippi on Saturday in the SEC-Big 12 Challenge.
Kansas travels to Rupp Arena on Saturday to play No. 8 Kentucky.
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