Jackson, the Rams' career rushing leader, plans to void the final year of his contract to become a free agent March 12, the St. Louis Post-Dispatch reported Monday.
Jackson has topped 1,000 yards rushing for eight seasons running. But with his 30th birthday approaching in July, the Rams appeared uninterested in giving Jackson a lucrative extension beyond the 2013 season. When the sides were unable to reach agreement before last season, the Rams gave Jackson the ability to void his deal in March 2013.
Jackson is scheduled to earn $7 million in salary for the 2013 season. It's unclear whether the Rams would have kept Jackson on their roster at that price. The team drafted running backs Isaiah Pead and Daryl Richardson a year ago. Richardson in particular showed promise right away, rushing for 475 yards with a 4.8-yard average.
The Rams have initiated a youth movement under coach Jeff Fisher and general manager Les Snead. They have the NFL's youngest roster at present, according to Elias Sports Bureau.
Jackson has 2,395 carries for 10,135 yards and 56 touchdowns over his career, but he has never played for a winning team in the NFL.