Miami Dolphins running back Alexander Mattison (neck) was officially placed on injured reserve on Monday. Mattison injured his neck during a preseason game against the Chicago Bears on Sunday and later went for surgery.

The Dolphins immediately got to work on finding new running backs this preseason amid Alexander Mattison’s season-ending injury.

The Miami Dolphins placed Alexander Mattison on injured reserve Monday after the veteran running back suffered a season-ending neck injury in a preseason game against the Chicago Bears. Mattison left Sunday's game with a neck injury after being tackled on a 21-yard pass play and landing awkwardly on his head in the