"We had a good conversation with Keith and certainly understand his desire to seek an opportunity in another program," Stoops said. "He knows that we are supportive of him under any circumstance, whether it's here or at a different school. We want what's best for him.
"Keith worked very hard while he was here and put forth all the effort our coaches could expect. He contributed to our program with his character and dedication. Keith leaves with our appreciation and best wishes and we will do what we can to make this an easy transition for him."
Last season, as a true freshman, the Lowell, Mich., native played in OU's games against North Texas, Utah State and Tulsa. He completed 2-of-7 passes for 15 yards with no touchdowns or interceptions, and he rushed three times for 13 yards.
Bradford led the Sooners to the 2007 Big 12 Conference championship in his redshirt freshman season. He led the nation in passing efficiency, completed 69.5% of his passes and set an NCAA record for touchdown passes by a freshman with 36 against just eight interceptions.