Mays was released last week by Detroit before signing with the Raiders on Wednesday. He is reunited with defensive coordinator Ken Norton Jr., who was a coach at USC when Mays played there.
Mays has played 66 games the past five seasons for San Francisco and Cincinnati. He has 72 tackles, four passes defensed, one sack, one forced fumble and two fumble recoveries. He has spent time this offseason with Minnesota and Detroit.
Mays played primarily special teams last season for the Bengals.
The Raiders waived linebacker Chase Williams to make room for Mays.
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