Rams coach Jim Haslett claims that Steven Jackson's lingering thigh injury is related to his training camp holdout. "It happens all the time," Haslett said. "You can run all you want, you can lift weights all you want, but until you put pads on and you actually cut and move at full speed, you can't replicate that until you actually do it." Jackson held out for 27 days this summer. "That goes back to when I was playing," added Haslett, a former NFL linebacker. "Guys that don't go to training camp get hurt." Jackson will miss his fourth game in five weeks when St. Louis faces Chicago on Sunday.