The 28-year-old defender was released by the Miami Dolphins earlier this week. He signed a three-year deal with the Dolphins in 2012 but suffered a back injury early last season that forced him to miss the team's last 12 regular-season games.
Marshall hadn't missed a single NFL regular-season game prior to 2012.
San Diego—a team in desperate need of help in the secondary after ranking 18th against the pass a season ago—will mark the fourth NFL franchise Marshall has played for since 2010.
As NBC Sports' Pro Football Talk's Josh Alper points out, Derek Cox, Shareece Wright and Johnny Patrick were the only experienced defensive backs on the Chargers' roster prior to the Marshall signing.
A standout performer at Fresno State, Marshall was selected in the second round of the 2006 NFL draft by the Carolina Panthers. He went on to play five seasons with the Panthers before becoming an unrestricted free agent and signing with the Arizona Cardinals in 2011.
Following one season in Arizona, in which he recorded 69 total tackles, defended 11 passes and tallied three interceptions, Marshall made the move to Miami.
The Los Angeles native has very limited NFL postseason experience, appearing in just one playoff game with the Panthers in 2008. Marshall has 452 total tackles, 18 interceptions, seven sacks and two touchdowns in 100 regular-season appearances since entering the league seven years ago.
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