Alex Green has failed his concussion test ahead of the Green Bay Packers' game against the Tennessee Titans.
The running back leads the Packers in rushing yards, with 464 this season.
Green sustained the head injury in the Packers' win over the Chicago Bears last weekend, which sealed the NFL North title for the side.
Ryan Grant will make his first start for Green Bay in place of the 24-year-old.
All players must complete a series of tests set by the league before they are allowed to return from a concussion.