Dolphins running back Alexander Mattison’s season is over.

Mattison underwent season-ending neck surgery on Sunday in Chicago, according to Adam Schefter of ESPN. Mattison hurt his neck during Sunday’s preseason game against the Bears and had the surgery at a nearby hospital after the game.

The seriousness of the injury stands in contrast to what Dolphins head coach Mike McDaniel said after the game. McDaniel was asked about Mattison and did not sound overly concerned.

“He’s doing well. He had some neck and shoulder soreness, but we’ll find out more in the next couple of days,” McDaniel said of Mattison.

With Mattison out, the remaining running backs in Miami are De’Von Achane, Jaylen Wright and rookie Ollie Gordon. Jamaal Williams is also working out for the Dolphins today.

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