The loss extended the misery for Illinois (13-10, 2-8). The Illini have lost eight straight. That streak started with a 95-70 blowout by the Badgers in Madison on Jan. 8.
Wisconsin's biggest edge was from 3-point range. The Badgers were 10 of 23. Illinois was just 4 of 10 on 3-pointers.
Four of Wisconsin's 3-pointers were Dekker's. They included a pair over the final three minutes that kept the Illini at arm's length. The last of them made the score 66-57 with 2:38 to play and gave the Badgers a comfortable edge.
Rayvonte Rice led Illinois with 24 points and nine rebounds.
The 3-pointers were the biggest difference, turning what had been a game of one- and two-point leads for much of the first half.
But the Badgers were also effective from the free throw line, and they were efficient in getting there. Wisconsin hit 80.8 percent of their free throws, going 21 for 26.
The only answer for Illinois, short on big men with experience, was Rice. The 6-foot-4 shooting guard leads the Illini in rebounding with 5.8 per game coming in. His nine boards were nice, but Illinois had just 25 on the night.
Wisconsin was the team that started Illinois losing streak. The Badgers buried the Illini with a 20-0 run on the way to 95-70 blowout back on Jan. 8 in Madison, and Illinois hasn't come closer to a win than a pair of six-point losses since then.
But the Badgers have struggled since then, too, losing five of six and falling out of The Associated Press Top 25.
The chances for Illinois to end the streak were there but those opportunities slipped away.
Down 49-46 with just over 10 minutes to play, Illinois stopped the Badgers on three straight possessions and couldn't score on any of them.
Brust sank two free throws and the Badgers again had breathing room, 51-46 with 7:56 to play.
Early in the game Illinois hung with the Badgers and traded leads.
After he tied the game at 23 with a free throw, Jackson urged his team to play a little defense.
"Let's get a stop!" he yelled as the Badgers set up under their own basket.
And after a single free throw from Tracy Abrams, they did. A bunch of them, in fact.
The Badgers used a 9-0 run late in the first half to put some space between themselves and Illinois.
Dekker opened it with a long 3-pointer with 3:36 left in the first half that drew some oohs from the crowd and Rice ended it with a jumper just over two minutes later. Wisconsin was up 33-26.
Heavy snow fell in Champaign Tuesday night, keeping the sparse crowd quiet much of the night.
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