The Jaguars received cornerback David Jones and a conditional draft pick in the deal, completed after teams made final cuts to get down to the 53-man roster limit.
Nelson was the 21st overall pick in 2007 out of Florida. He had an impressive rookie season — 82 tackles, five interceptions, two forced fumbles and a sack. Since then, he's had only two interceptions and his tackles total has dropped.
He shifted positions at Jacksonville after starting as a roaming safety. He spent time at cornerback and was part of nickel pass defenses. The three-year starter lost his job this year, playing at safety with the reserves during preseason games.
The Bengals were looking for depth at safety after Gibril Wilson damaged ligaments in his left knee during the preseason and was placed on injured reserve.
Jones was New England's fifth-round draft pick out of Division II Wingate in 2007. The Bengals claimed him off waivers that year. He was primarily an extra cornerback in three seasons with Cincinnati, starting seven games in 2008 after Johnathan Joseph got hurt. He has not intercepted a pass.