St.. Louis Rams quarterback Sam Bradford left Sunday's game against the Carolina Panthers on a cart with a left knee injury, and he was headed for an MRI exam Sunday night.
ESPN.com and NFL.com both reported the injury appears to be serious.
"I don't have any information on Sam right now," Rams coach Jeff Fisher said after the game in Charlotte, N.C. "We've done X-rays, we'll do an MRI tonight after we land (in St. Louis)."
Bradford landed hard on his knees near the sideline, when he was legally pushed to the ground by safety Mike Mitchell. Bradford was in bounds when hit, and Mitchell was not penalized on the play.
Offensive guard Harvey Dahl drew a flag for his retaliatory shove of Mitchell.
Kellen Clemens entered the game in the fourth quarter with the Rams trailing 30-15, and neither team scored again. Clemens completed two of four passes for 19 yards and was sacked twice.
Bradford went 21-for-30 for 255 yards with one touchdown pass and one interception. On the season, he is completing 59.5 percent of his passes for 1,432 yards with 13 touchdowns and three interceptions. Bradford has a 90.9 passer rating.