ALLEN PARK, Mich. (AP) Detroit placed cornerback Rashean Mathis on injured reserve, one day after the Lions ruled him out for Sunday's game at Green Bay because of a concussion.
Now his season is over. He started 36 games for Detroit in three seasons with the team.
Detroit also signed cornerback Crezdon Butler and signed safety Isaiah Johnson from the practice squad on Saturday. The Lions released linebacker James-Michael Johnson.
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Butler spent the 2015 training camp with the Lions before joining the Seattle Seahawks. He appeared in one game for Seattle.
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