The injury ended up being more severe than expected and he has not been able to play in '09 as originally planned.
Granger petitioned the NCAA in hopes of gaining a year of eligibility with an eye on the 2010 season, but the NCAA has come down with a ruling and he will not be granted a medical hardship.
"He has applied, but they have come back and denied it," OU head coach Bob Stoops informed on Tuesday afternoon. "It's not going to work, it's not going to happen."
In his career as a Sooner Granger has played in 38 games (11 starts) and accumulated 75 tackles, 15 tackles for a loss, and 3.5 sacks.
In 2007 he was recognized as a All-Big 12 second team selection by the coaches in the conference.
Stoops continued, "In the end it's very unfortunate for DeMarcus. He has fought through the back, but he has a part of a nerve that has not fully come back yet and they (doctors) think it will. It just hasn't in time and he has not been able to fire the one leg as strong or quick as he needs to. It's been frustrating.
"He has been a great teammate. He has been out there working up until last week. He has been trying to help, but has not been able to do it."