Indiana has fired defensive coordinator Doug Mallory and defensive line coach Jon Fabris, the school announced Friday.
The Hoosiers had one of the nation's most explosive offenses but finished last in the Big Ten in defense for the third straight year under head coach Kevin Wilson.
They allowed 38.8 points per game in 2013 and ranked 120th out of 123 FBS teams in total defense.
Mallory had served as Indiana's assistant head coach and defensive coordinator the past three years. He is the son of Bill Mallory, the Hoosiers' head coach from 1984 to 1996.
Brian Bennett of ESPN.com contributed to this report.