The Miami Dolphins added a power-running veteran to their running back room on Thursday, agreeing to a deal with Alexander Mattison, a person with knowledge of the agreement told The Associated Press. The person spoke to the AP on condition of anonymity because the deal had not been finalized.

The Dolphins and free agent RB Alexander Mattison agreed to terms. Here’s what to know and how he fits in Miami.

The Miami Dolphins are bolstering their backfield in free agency. The Dolphins agreed to sign veteran running back Alexander Mattison on Thursday, according to Fox's Jordan Schultz. Mattison is only 26 but is entering his seventh season in the NFL.

NFL free agency has begun, and we're keeping track of every major signing, trade and release of the 2025 offseason, with analysis from our NFL Nation reporters and grades from our experts. The new league year began March 12 at 4 p.m. ET, when free agent signings could become official. The first round of the 2025 NFL draft begins April 24 on ESPN.

Eichenberg’s versatility and familiarity with the Dolphins’ wide zone scheme and offensive line coach Butch Barry were likely big factors in his return.

The Miami Dolphins announced new contracts for four of their players who were set to become free agents Wednesday afternoon. New deals for safety Elijah Campbell and outside linebacker Quinton Bell were already reported ahead of the start of the new league year.