Jared Cameron has been placed on injured reserve after not playing since Week 3 due to a concussion.
Cameron has suffered four concussions in the past four seasons and is considering retirement.
Cameron has been seeing a concussion specialist in Pittsburgh. He said this week he was improving, and he hoped to return this season, but the Dolphins decided to replace him on the roster.
Cameron missed five games due to concussion issues in 2014, his last season with the Browns.
A Pro Bowl selection with Cleveland in 2013, Cameron has totaled only 43 catches and four touchdowns in two years with Miami.