 He was a key player of the "Blackshirts" (Nebraska defense) for the undefeated 1970 and 1971 teams, which won consecutive national championships.During Jacobson's three seasons on the Huskers (1969–71), Nebraska was 33-2-1, with records of 9-2, 11-0-1, and 13-0, and three consecutive bowl victories.The 38-6 victory in the 1972 Orange Bowl over #2 Alabama was the Huskers' 22nd consecutive win, and 32nd without a loss.