But Rush is back in the fold and he's looking to make up for lost time.
"It's tough coming back from an injury, so I feel like I have something to prove," Rush said. "I haven't made my mark at OSU yet. I'm just ready to play; I just want to have fun again. I've missed playing the game that I love."
This season might provide him the first opportunity to see substantial time on the field after playing sparingly in five games as a redshirt freshman in 2008.
Rush mentioned that he has yet to make his mark on OSU after wrapping up a stellar high school career in Killeen, Texas, where he was a consensus top 100 player in Texas and a nominee for the Old Spice Red Zone Player of the Year Award.
Rush said the trials he's faced in Stillwater have given him a new outlook and appreciation for football.
"Every day is like a gift now. I guess I can see it more now after having to sit in the stands for a year and watching the games," he said. "I have a different perspective that I think will make me a better player overall."
Cowboy head coach Mike Gundy said the 6-foot-4, 314-pound junior is slowly but surely working himself back into starting contention.
"He's doing good," Gundy said. "His shoulders are holding up, but when you've had an injury like his, you almost have to start from scratch. You're out a whole year but he's done very well up to this point and I expect him to continue to progress."
Gundy added he is excited to see what Rush will be able to accomplish now that he's back to full health, but Gundy did convey one factor that could prevent Rush from starting in the Cowboys' season opener against Washington State.
"He's got a good body and he needs to continue to develop himself mentally and get tough again," Gundy said. "When you lose a year as an offensive lineman, you have to go through that stage where you develop your toughness again and that's where he's at right now."
While Rush is working on re-establishing himself in the rotation, quarterback Brandon Weeden said what he has seen from Rush thus far suggests his time may come sooner rather than later.
"He's answered the call," Weeden said. "The offensive line is kinda playing musical chairs right now but I think he really wants that job and he's done really well and adapted to the system."