Ball, who will be a senior in the upcoming season, is considered a Heisman Trophy contender.
Madison police spokesman Joel DeSpain said Ball, who had been out with friends early Wednesday, appeared to have been the victim of an "unprovoked attack" by five men, the Wisconsin State Journal reported.
The running back sustained a series of kicks to the head and torso after he was jumped from behind as he walking home through a crime-plagued area near campus behind two companions, police said.
Ball was treated and released from a local hospital.
DeSpain said robbery didn't appear to be the motive in the attack and police were investigating whether he was targeted because of who he is.
"We will continue to evaluate him as we approach the start of fall camp this weekend," Badgers Coach Bret Bielema said. "I do expect Montee to make a full recovery."
Sources told the State Journal the team is concerned Ball sustained a concussion.