3 of the 4 remaining opponents are playing their best football of the season right now.

Utah: always hard for us, regardless of record or health.
Kansas: all of their loses were within 1 score except for their 11-point loss to TCU, and they lost close games to several good teams (UNLV, @Illinois, @ASU, @Kansas St.)
ASU: Scattebo looks scary. Watch this week's highlights against OK St., and you'll see a strong rush defense with a nicely balanced offense.
Houston: They looked horrible most of the season but just reeled of 2 straight quality wins @Utah and against K-State. They don't score many points, but they can been highly efficient on offense with good speed. They came back from down 10 in the 4th quarter to K-State.

I have no reason to think our boys won't be ready for all 4 teams, but what looked like a really easy back-end of the schedule is suddenly looking far more stout.