Giants running back Jalen Simmons gave everyone a scare when he remained on the turf, on his stomach, after being hit in the head.
He walked off slowly, escorted by athletic trainer Ronnie Barnes, to the locker room.
The Giants announced Simmons has a concussion.
Simmons, who is with his third team since entering the league in 2016, finished his night with six carries for 11 yards.
The Giants already were thin at the position, playing without first-round pick Saquon Barkley. They have three other running backs with carries against the Lions, including Jonathan Stewart, who had four carries for minus-1 yard.
