Denver Broncos cornerback Dominque Rodgers-Cromartie left Wednesday's practice on a cart with an injury suffered during a one-on-one drill.
Initial reports indicated he suffered a high ankle sprain, which could carry a two- to six-week recovery period depending on the severity.
"He has done it before, so I am not overly concerned," coach John Fox said. "But any time a player misses time I am concerned. We will just get him healthy and get him back out there."
Rodgers-Cromartie signed a one-year deal worth $5 million, making him the second-highest defensive player on the roster behind cornerback Champ Bailey.
"I just hope he is OK and we can get him back quick," Bailey said after practice. "This is a big year for Dominique Rodgers-Cromartie and our team, so we can't lose a guy like that."
He was able to walk off the field with an exaggerated limp before sitting near the sideline and waiting for medical attention. He appeared to have his knee and ankle examined.
Rodgers-Cromartie was participating in a coverage drill, matching up one-on-one with rookie Quincy McDuffie.
Rodgers-Cromartie, a former first-round pick of the Arizona Cardinals, spent the past two seasons with the Philadelphia Eagles.