Sean Lee wants to prove he's healthy a year after tearing his ACL for the second time in six years.

“I played on pretty torn ACL for a couple of years,” Lee said. “That’s what the main injury was with me coming in. The right [knee] was fine. But when I came back for that fifth year at Penn State, the third game in, I partially tore it. I took off about three games and then played with it. It would shift every once in a while. The further I got away from the injury, the less it would shift. It happened maybe a couple of times a season to maybe once or twice a season. I thought it would be fine and then when I slipped last year the knee went on me. It was a matter of time.”

Lee has been a highly productive linebacker for the Dallas Cowboys, but he's struggled to remain healthy.