The 6-foot-1, 207-pound Williams has appeared in 10 games over two seasons with Indianapolis (2012) and Arizona (2013) and seen time on offense (wide receiver), defense (cornerback) and special teams.
Manning played in two games for the Bears this season and saw time on special teams. He has appeared in eight games over three seasons with Green Bay (2012), San Diego (2013) and Chicago (2014).
The moves were announced on Wednesday.
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