WASHINGTON (AP) — Robert Griffin III had surgery Wednesday morning to repair a torn ligament and to determine whether there was any other damage in his ailing right knee.

A person familiar with the situation told The Associated Press that the procedure was expected to last about two hours. The person said orthopedist James Andrews planned to repair a torn lateral collateral ligament and examine the state of Griffin’s ACL.

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.

A torn LCL requires a rehabilitation period of several months, possibly extending into training camp and the start of next season. A torn ACL is a more severe injury, typically requiring nine to 12 months of recovery, although Minnesota Vikings running back Adrian Peterson made a remarkable return this season some eight months after tearing an ACL — and nearly broke the NFL’s single-season rushing record

Griffin was optimistic before he entered surgery, tweeting early Wednesday: “Thank you for your prayers and support. I love God, my family, my team, the fans, & I love this game. See you guys next season.”

Griffin reinjured his knee at least twice in Sunday’s playoff loss to the Seattle Seahawks, prompting a national debate over whether coach Mike Shanahan endangered Griffin’s career by not taking his franchise player out of the game sooner.

The first major injury to his knee came in 2009, when Griffin tore the ACL in the third game of the season while playing for Baylor. Griffin missed the rest of the year but returned in 2010 and won the Heisman Trophy in 2011.

Griffin sprained the LCL last month when he was hit by Baltimore Ravens defensive tackle Haloti Ngata at the end of a 13-yard scramble. Griffin missed one game and returned to play three more with a knee brace, his mobility clearly hindered.

Then, on Sunday, Griffin hurt the knee again as he fell awkwardly while throwing a pass in the first quarter against the Seahawks. He remained in the game, with Shanahan saying he trusted Griffin’s word that all was OK.

Griffin finally departed in the fourth quarter, after the knee buckled while he was trying to field a bad shotgun snap.

The No. 2 overall pick in last year’s draft, Griffin was one of several rookie quarterbacks to make an instant impact on the NFL this season. He set the league record for best season passer rating by a rookie QB and led the Redskins to their first NFC East title in 13 years.

But he also had to leave three games early due to injuries — two because of his knee and one because of a concussion — and missed a fourth altogether because of the knee.

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