A person familiar with the situation says Miami Dolphins rookie linebacker Raekwon McMillan will miss the entire season with a torn ACL in his right knee.
The person confirmed the diagnosis to The Associated Press on condition of anonymity Friday because the Dolphins have not commented publicly.
McMillan was the front-runner to winning the starting job at middle linebacker until he was hurt covering a punt early in Thursday's exhibition opener against Atlanta.
McMillan was taken in the second round with the 54th overall pick in the April draft after making 275 tackles in three seasons at Ohio State.
The loss of the promising rookie is the latest blow for the Dolphins in an injury-filled training camp.