The Sooners came with an overtime loss in the Rose Bowl (to Georgia) of playing for the national championship last season. That was with Heisman Trophy winning QB Baker Mayfield. Mayfield is gone. So is an All American tight end (Mark Andrews) and a left tackle (Orlando Brown)
New QB Kyler Murray may be a better baseball player (the Oakland A's gave him 4 million to dabble with a smaller ball). Murray has some miles. He started at Texas A&M (so did his dad Kevin), but he's not Heisman quality.
Defensively, there are still lots of wholes in the Sooner d, which second year coach Lincoln Riley must figure out. This doesn't mean OU will be also rans. They will be Top 10 good, just not Top 4 good.