TCU stayed put in the rankings at No. 20 this week after a 55-13 win over Portland State on Saturday.
In the AP poll, LSU took over the No. 1 spot with a convincing win over West Virginia.
Mountain West rival Boise State is No. 4 in the AP poll and No. 5 in the USA Today poll.
TCU takes on rival SMU next week at 2:30 p.m. at Amon G. Carter Stadium.