Nebraska head coach Scott Frost looks at the overcast sky before an NCAA college football game against Akron in Lincoln, Neb., Saturday, Sept. 1, 2018. (AP Photo/Nati Harnik)

FILE - In this Oct. 28, 2017, file photo, Iowa State running back David Montgomery runs from TCU defenders Travin Howard (32), Ty Summers (42) and Chris Bradley (56) during the first half of an NCAA college football game, in Ames, Iowa. Iowa State takes on South Dakota State on Saturday, Sept. 1, 2018, in Ames, Iowa. (AP Photo/Charlie Neibergall, File)

Appalachian State defensive back Clifton Duck trips up Penn State wide receiver Juwan Johnson after a reception during an NCAA college football game Saturday, Sept. 1, 2018, in State College, Pa. (Abby Drey/Centre Daily Times via AP)

Michigan State running back LJ Scott pauses before an NCAA college football game against Utah State, Friday, Aug. 31, 2018, in East Lansing, Mich. (AP Photo/Al Goldis)