Dominique Rodgers-Cromartie hurt
A team source told ESPN senior NFL Insider Chris Mortensen that it is a high ankle sprain.
Rodgers-Cromartie, who signed a one-year, $5 million contract with the Broncos this offseason, was carted off the field during practice after injuring his left leg.
Fox said there was no timetable for the cornerback's return, but he was hopeful he'd be ready to play by Week 1.
"He's done it before, so I'm not overly [concerned]," Fox told reporters. "But any time you miss time, I'm concerned."
ESPN senior NFL Insider Chris Mortensen contributed to this report.
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