Rams coach Jeff Fisher acknowledged the injury during his Monday evening news conference, stopping short of saying Wells' season was over but providing enough context to do the simple math.
"Scott's going to be down for four to six [weeks] now," Fisher said. "We're still evaluating it, but it's a four-to-six-week injury."
Fisher compared the injury to the one suffered by rookie safety T.J. McDonald in the first meeting against San Francisco on Sept. 26. That injury kept McDonald out for eight weeks and he returned after spending the required time on the injured reserve/designated to return list.
According to Fisher, Wells' fibula is not displaced and the process of evaluating what to do with his roster spot is ongoing.
Wells started the first 12 games of this season after an injury-plagued 2012 in which he only started seven games because of a broken foot and knee issues.
Tim Barnes filled in for Wells against the 49ers and is expected to make his first career start this week against Arizona.
"He played pretty well," Fisher said. "Tim, he's a pro, he prepares. He gets a minimal amount of reps on the practice field and he played well with Scott being down. So, Tim will be our guy."