The win could land Indiana (16-14, 7-12 Big Ten) a low-seed berth in the NCAA Tournament.
Rob Phinisee added 17 points and Justin Smith 15 points for the Hoosiers.
Ayo Dosunmu led the Illini with 16 points, while Giorgi Bezhanishvili and Trent Frazier added 15 and 13 points, respectively.
The loss closed out the home season for Illinois (11-19, 7-12).
The Hoosiers were in control for most of the game, leading by as many as 22 points before Illinois went on a 6-0 run to close to within 13 points at 80-67 with 5:22 left. But Indiana took advantage of an obviously tired Illinois defense and iced the game.
Despite hitting 7 of 13 three-pointers in the first half, Illinois seemed out of synch and trailed 52-42 at the half.
THE BIG PICTURE
Thursday’s game had conference tournament implications for both teams.
Indiana likely will have a first-round bye in the tournament, while Illinois could find iteslef playing next Wednesday.
Indiana’s wins last week at home over Wisconsin and Michigan State have thrust the Hoosiers back into the NCAA Tournament conversation, but they would need to beat Rutgers at home to have a chance.
Indiana: Ends the regular season hosting Rutgers on Sunday.
Illinois: Travels to Penn State Sunday to close its regular season.