Morgan had 5 concussions in 7 season with Carolina, and began to turn the corner last year, until tearing his Achilles in Week 4.
Carolina drafted Morgan in 2001 out of the University of Miami in the first round. He recorded 452 tackles, seven sacks, four forced fumbles and five interceptions. He played in 59 games, all starts, and was voted to the Pro Bowl in 2004.
Morgan's agent Drew Rosenhaus told ESPN's John Clayton: "His injuries just weren't healing enough for him [to play]."
I hate it when guys have to retire under these circumstances, this is even worse because he was one of my favorite players.