Why we might be wrong: There’s too much to replace on defense. Replacing stars on defense hasn’t been a problem in years past, but there are too many unknowns this fall. The secondary includes converted safety Jonathan Nelson (or career reserve Jamell Fleming) at one corner, and undersized Demontre Hurst at the other. That’s an issue in a league that throws the ball as often as teams do in the Big 12. The secondary will get help from what could eventually be the best defensive line in the Big 12, including All-American candidate DE Jeremy Beal and sophomore DT Jamarkus McFarland—who the staff believes could have a similar impact as former OU greats Tommie Harris and Gerald McCoy.