Indianapolis, IN -- (Sports Network) - Indianapolis Colts safety Bob Sanders returned to full practice on Friday and is expected to see his first action of the season on Sunday at St. Louis.

The 28-year-old, who sat out Thursday's session to rest his knee, has missed the Colts' first five games of the season.

Defensive back Marlin Jackson (knee) missed the last three days of drills and was ruled out for the Rams game.

Jackson's backup Tim Jennings (calf) is questionable along with linebacker Freddie Keiaho (illness), offensive lineman Jamey Richard (illness) and running back Chad Simpson (illness).