Voltz suffered the injury during the third quarter of the Badgers 24–13 win over Illinois on Saturday.
Potrykus reports that redshirt freshman Michael Deiter, who came in after Voltz left the game, will start in place of Voltz.
“I think he has done a lot of really good things for us," head coach Paul Chryst said of Deiter. "I think he did a nice job finishing out the game [Saturday]."
Voltz, a junior, was a US Army All-American out of Barrington High School in Illinois.