TCU humiliated the Sooners, while the top-ranked Kentucky Wildcats were defeated on the road by Ole Miss.
Despite its championship pedigree and Playoff-level performances in recent years, Oklahoma has had poor performances.
But Saturday reminded us that, despite the fact that defensive expert Brent Venables has taken over the programme, old problems remain.
TCU shelled the Sooners 55-24 on the road, their second conference loss in a row.
The Sooners gave up explosive passing plays of 62 and 73 yards, as well as big rushing plays of 35, 36, 67, and 69 yards to a TCU team coached by pass-happy Sonny Dykes.
In a game that quickly became a farce, the Frogs scored 41 points in the first half.
It will be interesting to see where the Sooners offence goes from here, in addition to their defensive performance.
Dillon Gabriel, the quarterback, left the field with an apparent head injury after being hit high while sliding.
Later in the game, Damond Harmon went down for the Sooners with an apparent head and neck injury.