Dolphins make three roster moves before free agency

The Miami Dolphins made three updates to their roster just before the official start of free agency.

Miami re-signed linebacker Kelvin Sheppard, safety Michael Thomas and gave a second-round tender to restricted free-agent defensive end Derrick Shelby, the team announced. All three players were backups last season but provide quality depth on defense and special teams.

Free agency begins at 4 p.m. ET when players can officially sign contracts with teams.