Hangartner had been practicing with the first team at training camp. He has started 83 games, including 12 last season for the Panthers, during his eight-year career with Carolina and the Buffalo Bills.
Hangartner graded out as a bottom-five center last season, according to Pro Football Focus. The team drafted Edmund Kugbila from Valdosta State to compete with Hangartner, but he has been sidelined with a hamstring injury. The 31-year-old Hangartner was due to make $1.575 million this year.