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"Davis, 31, missed most of training camp as he rehabilitated from the knee surgery that limited him to only two appearances in 2004. He returned to practice toward the end of camp, when he was removed from the physically unable to perform list, and began the season as the Panthers' starter.
But in recent days, Davis has been hampered again by knee problems, and his right knee swelled considerably this week. When it did not respond well to treatment, the Panthers decided it was pointless for Davis to try to continue the season. It is not yet known if he will require further surgery to address his longtime knee woes.
Panthers general manager Marty Hurney, quoted by The Associated Press, called the move "disappointing," adding that the team's decision wasn't based on medical tests."