Kansas (19-13) used a 15-0 spurt spanning halftime to take control and advance to face fourth-seeded South Carolina on Monday at the Coors Events Center.
The Buffaloes (25-7) saw their first trip to the NCAA tournament in nine years come to an unexpected end.
All the more maddening, it came against their former foe from the Big 12 that always seemed to have their number.
The Buffs, ranked 19th, were favored, but they missed Rachel Hargis' presence in the post. The junior center sprained her right knee in practice a week ago and didn't play, robbing Colorado of an inside player to counter Kansas' size down low.
They also missed plenty of shots—Arielle Roberson and Chucky Jeffery, their two leading scorers, combined to shoot just 5-for-29 from the floor. Roberson finished with 11 points and Jeffery eight. Brittany Wilson also had 11 for the Buffs.
Chelsea Gardner and Charlicia Harper each scored 12 for the Jayhawks and Monica Engelman added 10 points.
Both teams were coming off a two-week layoff, having last played on March 9, but the Jayhawks shot 45 percent to the Buffaloes' 24 percent rate.
The Buffaloes raced out to a 14-4 lead, however, and it looked as if they were going to exact some payback for all those losses to Kansas back in their days in the Big 12.
Now a member of the Pac-12, the Buffs talked during the week about how excited they were to host the Jayhawks again even though Kansas beat them by double figures three times in their last year together in the same conference two years ago.
That year, they lost to Kansas 68-58 at home, 81-53 in Lawrence and 71-45 in the conference tournament.
"Oh yeah, we remember," said Jeffery, a senior guard. "All of us remember. As soon as our name and Kansas came up on the screen we all looked at each other and were like, 'This is our time, right here.' We're excited to have Kansas again.
"I think it's going to feel better playing on our home floor, like coach said, it's a comfort thing. They can bring as many fans as they need, but I think we're going to have a pretty good turnout ourselves."
The home crowd didn't help the Buffaloes, who saw their big lead wither away quickly as the Jayhawks closed the first half on a 33-13 run to take a 37-27 halftime lead.
This was just the third time all season the Buffs trailed at the half at home.
After making six of their first seven shots, the Buffaloes made just six of their next 35.
It started to get away from them late in the first half.
They were down just 30-27 when Engelman hit a jumper while Jeffery was whistled for the foul away from the ball.
Goodrich made both free throws and just like that, it was 34-27. Then, Harper hit a 3-pointer from the left side just before the buzzer to push the Jayhawks' lead to double digits at halftime.
The Jayhawks scored the first eight points of the second half to put this one away early.
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