The Green Bay Packers were without running back Eddie Lacy after he sustained a concussion on his first carry in the first quarter of Sunday's game at Lambeau Field.
A good seal from David Bakhtiari and Josh Sitton allowed Lacy a lane for a 10-yard gain on the first series, but he collided with Washington safety Brandon Meriweather, who appeared to collide with the 5-foot-11, 230-pound rookie with the crown of his helmet.
Veteran running back James Starks replaced Lacy, who will not return, according to the Packers.
Meriweather also left in the second quarter after knocking heads with Starks on a sideline carry. His status is uncertain.