The Dolphins only drafted four players this year, so there was a lot of room for them to add undrafted rookies to their offseason roster. They took advantage of that space to sign 21 of them on Friday. Quarterback James Blackman is one member of the group. Blackman played at Florida State for four seasons before moving on to Arkansas State. He completed 223 of 347 passes for 2,471 yards and 14 touchdowns last season and joins Mike White and Skylar Thompson behind Tua Tagovailoa on the Miami depth chart. Miami linebacker Mitchell Agude, Stanford cornerback Ethan Bonner, BYU running back Chris Brooks, Mississippi State defensive end Randy Charlton, Cal Poly wide receiver Chris Coleman, Western Kentucky wide receiver Daewood Davis, Michigan State tackle Jarrett Horst, South Dakota offensive lineman Alex Jensen, Jackson State linebacker Aubrey Miller, UCF defensive tackle Anthony Montalvo, Nebraska linebacker Garrett Nelson, USC defensive tackle Brandon Pili, Miami offensive lineman DJ Scaife, Kentucky safety Keidron Smith, Cincinnati tackle James Tunstall, Oklahoma punter Michael Turk, San Diego State offensive lineman Alama Uluave, Illinois State linebacker Zeke Vandenburgh, and Oregon safety Bennett Williams.