Dolphins sign LB James-Michael Johnson with Jelani Jenkins hurting

The Dolphins added to their linebacker group on Tuesday. Peter G. Aiken Getty Images

The Miami Dolphins' struggling run defense didn't get any help on Sunday with starting linebacker Jelani Jenkins suffering an ankle injury.

On Tuesday, the Dolphins brought in a player to help combat Jenkins' injury. The team announced that they've signed former fourth-round pick James-Michael Johnson and waived center Sam Brenner.

Johnson was a fourth-round pick of the Browns in 2012, starting eight games as a rookie. He was waived after the 2013 season. He'd make 10 starts over the course of the following three seasons for the Chiefs, Buccaneers and Jaguars.

He's played in three games this season but has yet to record a tackle. However, he has made 104 tackles in his career and forced two fumbles.