Lions sign Josh Johnson after head injury to Tom Savage

The Detroit Lions have signed quarterback Josh Johnson in light of a head injury to top backup Tom Savage, the team announced Saturday.

Savage was checked for a concussion after leaving the preseason opener Thursday night. Head coach Matt Patricia confirmed Saturday that the quarterback is in the concussion protocol, according to team writer Tim Twentyman.

Detroit worked out Johnson and former Pittsburgh Steelers pivot Landry Jones before electing to ink the former. Terms of the contract were not disclosed.

The first pick in last year's AAF quarterback draft before that league folded, Johnson saw NFL action for the first time in five years last season. The 33-year-old started three games for the Washington Redskins following injuries to Alex Smith, Colt McCoy, and Mark Sanchez.

The Lions will mark Johnson's 13th NFL team.