MORGANTOWN, W.Va. -- No. 1 Kansas turned sloppy, West Virginia sixth man Jaysean Paige played inspired, and the No. 11 Mountaineers seized early control of the Big 12.
Paige closed the night with a steal and breakaway dunk to give him 26 points, and forward Devin Williams contributed 17 points and 12 rebounds in a 74-63 upset that ended with students swarming the floor.
West Virginia (15-1, 4-0 Big 12) knocked off the Jayhawks for a third consecutive season.
"I was ready to play," said Paige, a guard who made five steals and shot 14-for-17 at the foul line. "When I had the opportunity, I drove it. That was the game plan, to take it at them."
Forward Perry Ellis' 21 points weren't enough to save Kansas (14-2, 3-1), which didn't approach its 88-points-per-game average, had a 13-game win streak snapped and sabotaged itself with a season-worst 22 turnovers.
Point guard Frank Mason committed seven of the giveaways to offset his 12 points, while guard Wayne Selden fumbled away six turnovers while scoring 11 points.
Some mistakes surfaced from West Virginia's full-court pressure; others were born of carelessness.
"We were atrocious offensively as far as taking care of the basketball," Kansas coach Bill Self said.
Mountaineers guard Jevon Carter played harassing defense on Mason and scored 10 points, including a curl-around 3-pointer that put West Virginia up 55-44 with 9:23 left. The Jayhawks didn't close to within single digits again until the final minute.
In winning their eighth consecutive, the attacking Mountaineers enjoyed a 47-21 edge in free-throw attempts, and thanks to Paige, a 40-10 edge in bench scoring.
"We beat a heck a basketball team. They're No. 1 in the country for a reason," Mountaineers coach Bob Huggins said. "This isn't going to happen to them very often, if ever again. They're good."
The game was a near-sellout, though for the second straight year, an untimely snowstorm and icy roads meant thousands of no-shows. The 12,000-plus who trudged in -- some not arriving until halftime -- made ample noise as their team became the last with an unbeaten record in Big 12 play.
"There's going to be a lot of teams that lose here," Self said.
Paige, after combining for seven points and six turnovers in two previous games against the Jayhawks, scored 17 in the first half to spark a 37-29 lead.
The Jayhawks had 12 turnovers by intermission, surpassing their per-game average. After one sloppy bounce pass from Mason caromed out of bounds, Self screamed at his point guard and stomped down the sideline.
"(Carter) was tremendous at taking Frank out of the game," Self said.
Ellis scored 11 and guard Devonte' Graham beat the halftime buzzer with a straight-on 3-pointer to keep Kansas close. However, West Virginia used three point-blank baskets to go up 43-30 early in the second half.
"They were so much more aggressive and quicker," Self said. "They played high above the rim, and we didn't. They beat us off the bounce whenever they wanted to."
NOTES: West Virginia was committing 24.4 fouls per game, third most in Division I, yet Kansas was whistled for 32 and West Virginia only 20. ... With traffic snarled by the storm, the Kansas team bus received a police escort yet still needed almost an hour to make the 2-mile drive from its hotel to the coliseum. ... West Virginia G Daxter Miles (ankle) returned to the starting lineup after a one-game absence. He scored three points in 22 minutes. ... An incentive clause in Bob Huggins' revised contract from 2012 pays the West Virginia coach $25,000 for each regular-season victory over Kansas.