Ball State had taken a 30-29 lead just 15 seconds earlier when Kelly Page connected with Torieal Gibson on a 10-yard touchdown pass and MiQuale Lewis ran for a two-point conversion.
Opelt went 30 of 38 for 422 yards for the Rockets (3-2, 1-0 Mid-American). Williams and Tom Burzine each caught two TD passes, and Eric Page had another. Williams reeled in 10 passes for 231 yards, and Page caught 11 for 132.
Kelly Page was 25 of 41 for 234 yards for the Cardinals (0-5, 0-1), who dropped their homecoming game. Page threw scoring passes to Gibson and Briggs Orsbon, and Lewis ran for another. Ian McGarvey kicked three field goals, though his streak of extra points was snapped when he missed the kick after Lewis' TD.