The Jaguars originally selected Sims-Walker in the third round of the 2007 NFL Draft. In three years in Jacksonville, Sims-Walker caught 122 balls for 1,648 yards and 14 touchdowns. He had a career year for the Jaguars during the 2009 season when he caught 63 passes for 869 yards and seven touchdowns.
Sims-Walker had 139 yards on 11 receptions for the Rams this season, but was released on Monday after St. Louis traded for wide receiver Brandon Lloyd.
The 26-year-old Rucker has spent time with Cleveland, Philadelphia, Tampa Bay and Dallas. He has two receptions for 17 yards in 11 career games.