According to local reports, Lincoln police said Dennard was fighting a man outside a downtown bar when they tried to take him into custody.
Dennard allegedly pushed and punched an officer in the face, and police say it took four officers to take him into custody.
He was arrested on suspicion of third-degree assault on an officer and resisting arrest, and also third-degree assault in connection with the bar fight. The officer suffered minor injuries but did not seek medical attention, police say.
A first-team All-Big Ten selection in 2011, Dennard is projected as a second- or third-round pick in next week's NFL draft.
He recorded 31 tackles and six pass breakups, but his career ended on a down note as he was ejected for fighting with South Carolina's Alshon Jeffery in the Capital One Bowl.