MANHATTAN, Kan. -- As the final seconds ticked away on the massive new video board hanging from the rafters, an ocean of purple-clad Kansas State students began to spill onto the floor.
In a season full of failures, the Wildcats finally had reason to celebrate.
"I've talked all season about not dwelling on the past, not thinking about the future, focus on today," Kansas State coach Bruce Weber said, "and I think they did that."
Williams finished with 15 points in his final regular-season game against the Jayhawks, and Thomas Gipson added 12 points as the Wildcats (14-15, 7-9 Big 12) overcame an eight-point, second-half deficit to beat their bitter rival for only the fifth time in the past 54 meetings.
The Jayhawks (22-6, 11-4) trudged off the court as students poured from the stands into a mad pile, celebrating the biggest highlight of what has been a dreary season in Manhattan.
Weber even had to shield Kansas counterpart Bill Self from the crush of fans.
"I wasn't nervous for me, but there were several students that hit our players -- not saying with fists, but you storm the court, you run in, you bump people," said Self, whose team watched the Wildcats storm the court against them last year, too.
"Somebody is going to hit a player, the player is going to retaliate, you're going to have lawsuits -- it's not right," Self said. "At least (celebrate) around center court."
The Wildcats had lost seven of their last eight games amid suspensions and strife, and it appears a lock that their string of eight straight 20-win seasons will end. But at least for one night, against their biggest foil, they looked like a Top 25 team in their own right.
"It's good. We got them two years in a row," Williams said. "Like Coach said, it's just good for the fans, alums, all the students. It's a big-time win for everyone."
Perry Ellis had 24 points to lead the Jayhawks, whose lead over Iowa State in the league race was whittled to a half-game. Kelly Oubre Jr. also had 14 points.
Kansas State never allowed the Jayhawks to pull even in a tense final few minutes.
After Oubre made the first of two foul shots to cut Kansas' deficit to 64-61, Williams made two free throws at the other end. And when Brannen Greene scored with just under a minute left to make it 66-63, Williams knocked down a 15-footer to help wrap up the victory.
Johnson, who had played just 10 minutes total in the Wildcats' last two games, provided the surprising lift. He hit a pair of 3-pointers on his way to 10 first-half points, helping Kansas State to overcome a slow start and cut into an early Kansas lead.
A silly foul on the Jayhawks' Landen Lucas with 1.3 seconds left sent Williams to the foul line, and he made both shots to give Kansas State a 31-30 lead at the break.
The Jayhawks made another big run to start the second half, but a missed dunk by Ellis proved pivotal when Johnson scored at the other end. Instead of the Jayhawks taking a 43-33 lead, the Wildcats had trimmed the lead back to six points and had the momentum on their side.
Johnson added another 3 as the shot clock expired to knot the game 53-all, then scored again when the Jayhawks were called for goaltending as the Wildcats pulled ahead.
Kansas State never trailed again, beating the Jayhawks for just the fourth time in 27 meetings at Bramlage Coliseum.
"We just came out fighting," Williams said. "They're the first-place team in the league so they get everybody's best shot. We gave them our best shot tonight."
Weber showed his team a video of last year's victory over Kansas -- complete with the court-storming -- as motivation. "I said, `You can have your own special moment," Weber recalled.
One member of the Kansas State student section was taken from the crowd on a stretcher during a late timeout. A school spokesman said the student suffered a seizure and was taken to the hospital, where he was resting comfortably.
Kansas: The Jayhawks dropped to 8-6 away from Allen Fieldhouse, including 5-5 in true road games. ... Frank Mason III was held to four points on 1-for-8 shooting.
Kansas State: The Wildcats won despite getting outrebounded 37-28. ... Kansas State had averaged 52 points in its last three games.
Kansas returns to Allen Fieldhouse to face Texas on Saturday.
Kansas State welcomes No. 12 Iowa State to Bramlage Coliseum on Saturday.
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