Long, 29, is a four-time Pro Bowl lineman and former No. 1 overall pick, drafted by the Dolphins in 2008. He appeared in just seven games last season after tearing his ACL in October. He tore the same ACL in 2013.
The Rams also released center Scott Wells, who started all 16 games last season. Wagoner reported the two moves will save St. Louis about $12 million in cap space. Both players had upcoming contract deadlines that would increase their cap numbers substantially. He also reported there is a possibility the Rams and Long could re-open contract talks as the lineman's rehab progresses.
Long, then regarded as one of the best offensive tackles in the league, signed a four-year, $36 million deal with the Rams in 2013.
- Jeremy Woo