Last year, Barner was drafted in the sixth round by the Panthers. The 25-year-old Barner played in eight regular-season games and one playoff game with the Panthers.
He finished his collegiate career at Oregon ranked second in school history in yards rushing (3,623) and tied for second with 41 touchdowns rushing.
As a senior in 2012, Barner earned first-team All-America honors by rushing for 1,767 yards (second most in school history) and 21 touchdowns (tied for most in school history).
''Kenjon will hopefully bring some depth to both our running back and return positions,'' coach Chip Kelly said.
''He's obviously a guy I know really well from Oregon, where he had a very productive career. He has a lot of speed, explosiveness and had a knack for making some really big plays.''
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