Chattanooga athletic department spokesman Jay Blackman confirmed Friday that Bennifield would miss four games and that sophomore Nick Tiano will take over as the Mocs' starting quarterback.
The Chattanooga Times Free Press first reported Bennifield's situation.
Chattanooga opens its season Saturday against Jacksonville State at Montgomery, Alabama.
Bennifield, a senior from Lovejoy, Georgia, completed 64.4 percent of his passes for 2,622 yards with 26 touchdown passes and seven interceptions last season as Chattanooga went 9-4 and earned a third straight Football Championship Subdivision playoff appearance.
Tiano transferred to Chattanooga after playing for Mississippi State last season. He played five games for Mississippi State but attempted only one pass.