The Rams decided to pick up 23-year-old Young one day after he was released by the Lions despite a controversial end to his stint in Detroit.
He missed Detroit's final six games in 2012 after getting into a fight with wide receivers coach Shawn Jefferson along the sidelines during Detroit's Nov. 11 loss to Green Bay.
Young was sent home from practice by head Coach Jim Schwartz shortly thereafter and was later placed on injured reserve for the rest of the season.
He ended the season with 33 catches for 383 yards and four touchdowns after a dazzling 2011 rookie campaign during which he hauled down 48 passes for 607 yards and six touchdowns.
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