Detroit Lions outside linebacker Ernie Sims left during the third quarter of Sunday's 32-20 loss to the Seattle Seahawks with a hamstring injury suffered trying to track down Seattle running back Julius Jones.
Sims appeared to hurt his right leg, although the Lions didn't specify the injury. He did not return to the game.
Sims was chasing Jones at the front-end of a screen pass that went for 49 yards. After laying on the field for several minutes, Sims slowly walked to the Lions bench. He had three tackles.
He was replaced by DeAndre Levy.
Detroit cornerback William James was also shaken up later in the quarter after a hard collision with receiver T.J. Houshmandzadeh. He returned in the fourth quarter.
The Associated Press contributed to this report