Ridley, who spent his first four seasons with New England, agreed to terms on a one-year contract last week and the Jets made the signing official Monday. Ridley played in six games last year before tearing his right anterior cruciate ligament.
He has 2,817 yards rushing and 23 receptions for 146 yards. Ridley's best season came in 2012, when he ran for 1,263 yards and had 12 touchdowns. He adds depth to a running back group that includes Chris Ivory, Bilal Powell and Daryl Richardson.
Mays has 211 defensive tackles and 29 more on special teams in seven NFL seasons. He played for Kansas City last year, and has also been with Philadelphia, Denver and Houston.
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