Alexander Mattison will not be available to the Dolphins in 2025. The veteran running back is dealing with a neck injury which will require season-ending surgery, ESPN’s Jeremy Fowler reports. 
Mattison was injured during yesterday’s preseason game against the Bears. He was transported by ambulance to a Chicago hospital, and Fowler’s colleague Adam Schefter reports the procedure took place shortly thereafter. A 2025 free agent signing, Mattison will now hit free agency next spring after a missed campaign.
Over the course of his five-year Vikings tenure, Mattison operated at first as Dalvin Cook‘s backup. Minnesota moved on from Cook ahead of the 2023 campaign, during which Mattison took on RB1 duties. The 27-year-old set a career high in carries (180) and yards (700) but his 3.9 yards per attempt average left plenty to be desired. Mattison spent 2024 with the Raiders, logging seven starts as part of an offense which struggled to find any success on the ground. As expected, a poor showing hindered his market value.
Mattison took a one-year Miami pact worth $1.38MM in March. That move set him up to handle a role backing up De’Von Achane in the Dolphins’ backfield, one which will be without Raheem Mostert or Jeff Wilson in 2025. Mostert was released, while Wilson remained unsigned until recently. Losing Mattison will leave the Dolphins short on experience behind Achane, 2024 fourth-rounder Jaylen Wright and sixth-round rookie Ollie Gordon.
Miami entered Monday with nearly $12MM in cap space. As a result, finances will not be an issue if a free agent addition is to be pursued. Achane is not in danger of losing his starting spot, of course, but healthy depth would be welcomed in the wake of today’s news. Mattison, meanwhile, will turn his attention to the recovery process ahead of free agency in 2026.