Chris Long and Sam Bradford -- key elements to the Rams' chances in Week 13 -- both missed practice earlier this week with re-aggravations of their respective ankle injuries. Bradford has already missed two games, forcing the Rams to start A.J. Feeley twice in his place this season.
Long, the Rams' leading pass rusher with 10.0 sacks, has not missed a game in 2011, but would be followed by DE Eugene Sims if he cannot go on Sunday.
The Rams have already ruled out backups Josh Hull and Mark LeVoir, who are suffering from hamstring and pectoral issues respectively. Meanwhile, starter Justin King and Brit Miller seem poised to play on Sunday, barring any unforeseen setbacks.
Stay tuned to SB Nation St. Louis for more updates on the Rams and all matters St. Louis. For more on Sunday's game, check out Turf Show Times, SB Nation's St. Louis Rams blog, and Niners Nation, SB Nation's San Francisco 49ers blog.