Rams coach Jeff Fisher said RB Zac Stacy sprained ankle late in game and that's why they went with Richardson in closing moments.
Earlier reports Monday said Stacy suffered a low ankle sprain, but at Fisher's press conference later in the day, he said Stacy was still undergoing tests. Stacy was having a pretty big game against a tough Seattle defense (26/134) before the injury. Daryl Richardson, who played on the final drive, would likely get a bulk of the work if Stacy can't go. But Stacy's performance last night against the Seahawks should help him remain the starter - as long as he's healthy enough to play. This week the Rams take on the Titans. Look for another update after the Rams injury report comes out Wednesday.