Manning announced his retirement Tuesday, the Houston Chronicle reports. A second-round pick in the 2006 NFL Draft, Manning spent five seasons with the Bears and four with the Texans, starting 96 of the 128 games he played. He never brought much to the table from an IDP perspective, but he was a solid cover safety who also worked as a kick returner throughout much of his career. Manning could probably still be of some use to an NFL team, so it's possible he eventually changes his mind about retirement.