Wisconsin's Robert Wheelwright can't hang onto a pass in front of Iowa's Greg Mabin during the first half of an NCAA college football game in Madison, Wis., on Saturday, Oct. 3, 2015.
Wisconsin fell out of The Associated Press college football Top 25 after a loss to Iowa on Saturday.
Iowa jumped onto the list at No. 22, its first time in the ranking since November 2010. The Badgers were ranked No. 19 last week after ranking No. 20 in the preseason poll, No. 24 in Weeks 2 and 3, and No. 22 in Week 4.
Ohio State remained No. 1, while No. 2 TCU and No. 3 Baylor edged forward, No. 4 Michigan State slipped and No. 5 Utah and No. 6 Clemson took big jumps.
No. 13 Northwestern and No. 18 Michigan brought the Big Ten's total in the poll to five, one fewer than the SEC and tied with Pac 12.
THE AP TOP 25 POLL, WEEK 6
1. Ohio State (5-0)
2. TCU (5-0)
3. Baylor (4-0)
4. Michigan State (5-0)
5. Utah (4-0)
6. Clemson (4-0)
7. LSU (4-0)
8. Alabama (4-1)
9. Texas A&M (5-0)
10. Oklahoma (4-0)
11. Florida (5-0)
12. Florida State (4-0)
13. Northwestern (5-0)
14. Mississippi (4-1)
15. Notre Dame (4-1)
16. Stanford (4-1)
17. USC (3-1)
18. Michigan (4-1)
19. Georgia (4-1)
20. UCLA (4-1)
21. Oklahoma State (5-0)
22. Iowa (5-0)
23. California (5-0)
24. Toledo (4-0)
25. Boise State (4-1)
Others receiving votes: Oregon, Duke, Houston, Temple, Memphis, Navy, Arizona State, Mississippi State, West Virginia, Texas Tech, BYU, Kansas State and Missouri.
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