Reisner hit from 36 yards with eight seconds left on the clock. Minutes earlier he missed a 50-yarder that would have put Illinois on top.
O'Toole relieved an ineffective Wes Lunt late in the first half. O'Toole finished 18 of 25 for 157 yards and a touchdown for Illinois (5-6, 2-5 Big Ten).
Mike Dudek had 11 catches for 115 yards for Illinois.
Penn State running back Akeel Lynch carried the ball 28 times for 137 yards and a 47-yard touchdown.
PSU's 46-Hour Dance Marathon Raises $13 Million
BIG TEN SCOREBOARD
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