Clemson (6-1) dropped six spots in both the AP and Coaches' Polls Sunday after the 51-14 loss at home to new No. 3 Florida State (6-0).
They fell seven spots in the Harris Interactive (a BCS component) to No. 10, which was released later in the afternoon.
Clemson's seven-week run in the top-five was its longest since 1981.
In the Coaches, Alabama holds the top spot (57 first place votes), followed by Oregon (4), FSU (1), Ohio State, Baylor, Miami, Missouri, Stanford, Texas Tech, and rounding out the top-10, Clemson.
Four more top-10 teams fell this weekend, which dropped UCLA to No. 11, LSU to No. 13, Texas A&M to No. 15 and Louisville suffering the biggest drop to No. 16.
The Coaches Poll is one of two human polls that figures in the BCS (Harris Interactive the other). Those two make two-thirds and the average of six computer rankings will complete the make up of the first BCS standings tonight.
In the AP, the Tigers come in at No. 9, ahead of Texas Tech (7-0). The only change in the AP top-five is Missouri (7-0) ahead of Baylor (6-0).
FSU garnered two first place votes and sits 81 points behind Oregon for No. 2 in the Harris. They are 72 points behind the Ducks in the Coaches and are above Oregon in the Sagarin computer ranking. That complete top-10 is: Alabama, Oregon, FSU, Ohio State, Baylor, Missouri, Miami, Stanford, Texas Tech and Clemson.
Future Tigers' opponent South Carolina dropped to No. 20 in all polls after a loss at Tennessee this week. Georgia dropped completely out after suffering a loss at Vandy.