A short jumper by Alando Tucker pulled the Badgers within two points with 10:27 remaining in the game, but an 11-1 Illinois run over the next 3:10 built a cushion that never again fell below nine.
After a Brian Butch free throw cut the lead to single-digits with 2:18 remaining, Illinois forward Brian Randle collected the biggest of his game-high 13 rebounds. A Rich McBride 3-pointer bounced over a Wisconsin defender and into the hands of Randle before Jamar Smith made two free throws to permanently restore the double-digit advantage.
To get the best of their hosts, Illinois dominated the boards all evening, pulling down 43 to Wisconsin's 28 – including 15 offensive rebounds to just 6 by UW.
"They were pretty active," UW coach Bo Ryan said. "There was a couple there at the end where we cut it to six or eight and we had a chance to get a rebound. Long rebounds got touched, tipped, boom – and that counts as an offensive rebound. But they were good on the glass. They've been good all year, and we needed to be better."
The Badgers went on a 14-2 run to open up an 11-point lead midway through the first half. However, Illinois then countered with a 19-0 run of its own, during which the Badgers missed eight shots and committed five turnovers in 8:32 of play. Illinois then took a six-point advantage, 34-28, into the half.
Despite collecting two early fouls, Illini coach Bruce Weber elected to roll the dice and put senior forward James Augustine back on the floor as Illinois made its critical run. Weber also went with a smaller, quicker lineup to disrupt the Badgers on the offensive end.
"Our pressure picked up," Weber said. "Our defensive matchups, our kids started helping out on Tucker. I think our kids picked up the defensive pressure."
Wisconsin shot 36 percent from the field and just 3 of 20 from long range as it lost for the fourth time in five games for the first time since Bo Ryan's inaugural year at the helm in 2001-02.
The Badgers have now lost two of three at home for the first time in Ryan's tenure, after winning 52 of their previous 53 in Madison. The victory vaults the Illini (20-2 overall, 6-2 Big Ten) atop the Big Ten standings after downing the Badgers (15-6, 5-3) in Madison for the second consecutive season.
"For us to come up here and win two years in a row is an unbelievable accomplishment for me and for the program," senior guard Dee Brown said. "It's a great win for us."
The Badgers have struggled since one of their biggest strengths – their bench – has become a weakness with the loss of Marcus Landry and Greg Stiemsma for the season. The Illinois bench, essentially the 12 points from Jamar Smith on a perfect shooting night, was eight more than the entire Wisconsin bench produced.
While the dynamic duo of Alando Tucker and Kammron Taylor combined for 33 of the team's 51 points, Illinois had four players with more than a dozen points in what was a complete team effort. All-Big Ten guard Brown went just 6 of 18 from the field but he dished out seven assists as Randle, Smith and Rich McBride all made solid contributions.
"All those guys have stepped it up," Weber said. "Now we're not just ‘The Dee Team'. We've got a lot of players."
Ryan agreed with that assessment, also saying he has told people privately that he believed Illinois was the best team in the conference. After finally playing the Illini, he felt no different.
As for Wisconsin getting other players to step forward offensively, Tucker said he has confidence in his teammates and that he believes they have confidence in themselves. Ryan suggested that players need to start making the plays to snap them out of some poor shooting in recent games.
"If guys make shots," Ryan said. "That always did it for me. Get a steal and a layup. That would usually get me out of a slump."
For the second straight game Wisconsin trailed at the break and never regained the lead in the second half. Weber said he thought the Badgers started to doubt themselves a bit during that first-half run by the Illini.
Ryan added that in the second half his team tried to come out and take the ball in the paint to draw fouls on the Illini bigs. Jason Chappell in particular became frustrated after missing the team's first four shots of the second half and not getting a whistle in the paint. When that failed to work, the Badgers kicked the ball to the outside but as Ryan said, "we didn't hit there either."
Another punch to the stomach for the Badgers came during that 11-1 Illinois run after the Badgers had pulled within two. An Augustine dunk and a McBride 3-pointer provided five quick points that stretched the lead to 12 and deflated a raucous Kohl Center crowd that had previously risen to its feet.
"We worked our way back into the game and were feeling really confident at the time," Taylor said. "But to see them knock shots down and we come down and we miss our shots. You start to think about it. But we have to keep playing.
"We made our run and then they made theirs, and we just couldn't counter it."
Now at the midway point of the conference season, Wisconsin will attempt to get back on track with a visit to last-place Purdue (7-12, 1-7) on Saturday night at 7 p.m.