Riley was one of the four practice squad players protected by the Steelers last week. He was not among the team’s four protected members this week and the Cardinals seized the chance to pick him off the practice squad.
Riley made the Steelers initial 53-man roster before being released the following day after the addition of free agent defensive back Sean Davis. He was then re-signed to the team’s practice squad.
Riley has appeared in 43 career games with 19 starts over four seasons spent with the Tennessee Titans, New York Giants and Oakland Raiders.
Riley could be set to replace safety Jalen Thompson on the roster for Arizona. Thompson injured his ankle in the team’s win over the San Francisco 49ers last Sunday and did not participate in practice on Wednesday. If he heads to the injured reserve list, that would open a roster spot for Riley’s addition.