The Vikings signed rookie safety Theo Jackson off Tennessee's practice squad Tuesday.

Jackson was a sixth-round (204th overall) pick out of the University of Tennessee this year.

Ty Chandler was placed on injured reserve. The rookie running back suffered a thumb injury in Sunday's victory over the Bears.

Chandler, the fifth-round pick out of North Carolina, was injured while playing special teams in his second NFL game. He was a preseason standout with 15 carries for 113 rushing yards and a touchdown across three exhibitions.