Bradford limped out of Saturday night's 33-14 preseason win against the Browns with 8:19 to go in the first quarter after injuring the surgically repaired left knee.
After the game, Rams coach Jeff Fisher said more tests would be needed when the team returns to St. Louis on Sunday but also indicated that he was optimistic about what those tests will yield.
"I can't speculate but it appeared just to be a hyperextension of the same knee," Fisher said. "He's walking around fine inside right now. That's all I can tell you."
Bradford took what appeared to be a light hit from Cleveland's Armonty Bryant as he threw incomplete to tight end Jared Cook. Bradford shrugged Bryant off, but the defensive lineman made contact with the quarterback's left knee.
Bradford fell to the ground in pain as Rams doctors and trainers rushed to his side. He limped off the field under his own power but favoring the left leg as he went to the locker room for further examination.
Bradford was making his second start of the preseason after returning from a season-ending torn left ACL suffered against Carolina on Oct. 20, 2013. Bradford went 4 of 9 for 77 yards before leaving.
Information from ESPN.com's Nick Wagoner is included in this report.
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