Long, the No. 1 overall pick in the 2008 NFL Draft, was seen being worked on by Miami's training staff, and reportedly had his right knee brace removed.
The severity of the injury is currently unknown.
Long has been durable since being drafted by the Miami Dolphins, missing just two games throughout his four-year career. Despite his durability, Long has been nagged by various injuries, including knee, back and shoulder injuries in 2011.
Long is entering the final year of his contract. If the injuries continue to pile up for Long, the Dolphins could decide to let him walk after this season, rather than paying him a rich contract extension or tagging him with the franchise tag.
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