Montana State (4-3) built a 42-0 lead and gave way to backups from there. The Bobcats, who have struggled on defense, held ETSU (0-7) scoreless for first 51 minutes. The Buccaneers, however, gained nearly 400 yards and had 15 plays of 10 yards or more.
Prukop finished 15 for 21 and had 31 yards rushing on four carries. Jake Bleskin, who replaced him, led the Bobcats on a pair of scoring drives.
Jajuan Stinson and Tony Drew combined for 126 yards rushing on 17 carries to lead ETSU.