ST. LOUIS -- St. Louis Rams running back Steven Jackson missed practice Wednesday with lower back spasms, but expects to play Sunday against Seattle.
Jackson is second in the NFL with 1,031 yards rushing and 1,262 yards from scrimmage. He says he is day to day.
Jackson says he wasn't hurt on any particular play in a 21-13 loss to Arizona on Sunday, describing the injury as "wear and tear of the year."
Guard Richie Incognito was restricted to conditioning work and is likely to miss a fourth straight game with a foot injury.
Rookie offensive tackle Jason Smith did not pass baseline tests for what coach Steve Spagnuolo termed a mild concussion. Spagnuolo believed Smith would take the test again Thursday.