Trent Frazier scored 23 points, Kofi Cockburn added 17 and No. 18 Illinois surged in the second half to beat Indiana 74-57 on Saturday.
Cockburn also had eight rebounds, falling two short of tying Skip Thoren's school record for double-doubles. Thoren had 41 from 1963-65.
The Fighting Illini (17-5, 10-2 Big Ten) have won four straight overall and the last two on the Hoosiers' home floor.
Indiana (16-6, 7-5) was led by Race Thompson with 13 points and six rebounds. Xavier Johnson had 12 points, five rebounds and five assists on a day preseason All-American Trayce Jackson-Davis struggled again with foul trouble.
After leading almost the entire first half — most of it with Jackson-Davis on the bench for the final 15 1/2 minutes — Indiana had no answers in the second half for Frazier or Cockburn. Frazier scored 14 points after the break.
Illinois finally took its first lead since the opening minutes when Jacob Grandison made the second of two straight 3-pointers with 11:54 to play. His flurry started a 16-3 run that ended with Frazier's 3 with 7:45 left to give Illinois a 58-49 advantage.
The Fighting Illini continued pulling away over the final minutes as Indiana lost its second home game of the season.
Illinois: Coach Brad Underwood's team played its way back into the conference lead behind an incredibly stout defense and Cockburn's strong inside play. The defense played well yet again and Frazier's second-half barrage offset a mediocre day for Cockburn, who was 6 of 13 from the field. It's a combination that could lead Illinois to a conference crown.
Indiana: The Hoosiers have rebuilt their defense-first philosophy under new coach Mike Woodson — and it's worked wonders. But on Saturday, they wore down against a bigger, stronger opponent. Indiana has been on the cusp of cracking the Top 25 over the past few few weeks and now the wait will take a little longer.
Illinois was poised to move into the Top 15 after beating Wisconsin earlier this week and it only solidified it's case with Saturday's win. The only real question is how high the Illini will climb.
Illinois: Visits No. 4 Purdue in a key Big Ten clash Tuesday.
Indiana: Starts a two-game road trip Tuesday night at Northwestern.