Mike Dudek set up Illinois' winning drive with a 52-yard punt return to the Ball State 35. Quarterback Chayce Crouch hooked up with receiver Malik Turner for a 25-yard completion, and Epstein finished the drive with consecutive runs, including the winning touchdown,with 2:06 left.
Ball State drove inside Illinois territory in the final minute, but the Illini blocked Morgan Hagee's 54-yard field goal attempt to seal the win.
In addition to his impactful punt return, Dudek caught a 16-yard touchdown pass from Crouch in the first half.
Crouch completed 10 of 19 passes for 145 yards with a touchdown and an interception. Epstein carried 11 times ofor 54 yards.
Ball State freshman tight end Nolan Givan caught an 8-yard touchdown pass from quarterback Riley Neal in the first quarter that gave the Cardinals a 7-6 lead.
Illinois answered with a 12-play, 69-yard drive, capped by a 6-yard touchdown run by Epstein that gave the Illini the lead back.
Illinois tacked on a 40-yard field goal from Chase McLaughlin late in the first half to send the Illini into the locker room with a 16-7 lead.
Ball State wasn't going away, though, and opened the third quarter with consecutive, long touchdown drives. Malik Dunner's 3-yard touchdown run capped a 15-play, 75-yard drive for the Cardinals. James Gilbert finished off the Cardinals' next drive with a 3-yard touchdown run that put Ball State ahead 21-16 heading into the fourth quarter.
Expectations are once again low for the Illini, entering their second season under coach Lovie Smith. Illinois went 3-9 last year and was picked to finish in the bottom of the Big Ten West Division, along with Purdue, by the media in the offseason.
Ball State went 4-8 last season and was picked to finish last in the MAC West Division.