Idaho State backup quarterback Brad Kragthorpe has left the program for personal reasons, football coach Mike Kramer announced Wednesday.

Kragthorpe, from Tulsa, Okla., was a redshirt freshman last year.

"We wish Brad the best of luck in the future," Kramer said. "He represented our program with class and integrity this last year and we wish nothing but the best to him and his family."

Justin Arias and Riley Sessions, who just returned from his LDS mission, will assume the backup roles behind starting quarterback Kevin Yost.

Kramer also announced Roger Cooper has been hired as Idaho State's new running backs coach. Cooper replaces Ryan Smaha, who accepted a position at Weber State.