WASHINGTON (AP) - A person familiar with the situation says the surgery on Robert Griffin III's knee revealed damage to the ACL.
The Washington Redskins quarterback had surgery Wednesday morning to repair a torn lateral collateral ligament in his right knee.
The procedure also examined Griffin's ACL, which he tore while playing for Baylor in 2009. Another torn ACL would complicate Griffin's chances of returning by the start of next season.
The person spoke on condition of anonymity because the Redskins had not made an announcement about the latest details surrounding the rookie quarterback's injury.
Griffin sprained the LCL last month and reinjured the knee in Sunday's playoff loss to the Seattle Seahawks.
Follow Joseph White on Twitter: http://twitter.com/JGWhiteAP
Online: http://pro32.ap.org/poll and http://twitter.com/AP-NFL