Poor shooting led to an up-and-down, low-scoring game in which neither team could fully seize control until late.
It took overtime play, but Illinois prevailed 83-80.
Hoosiers rolled to 52-35 home victory.
Tigers win in Bloomington for first time since 1953
Top seeded Hoosiers win 80-64 to advance to semifinals.
The Illini trailed 41-29 at halftime and by double digits for most of the second half before closing the game on a 13-2 run over the final 3:36.
Indiana spoils Homecoming in Champaign 31-17
Teams square-off Saturday in Champaign.
Marvin McNutt sets school record for TD catches