Meanwhile, 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. 11 Florida made the biggest leap forward, jumping 14 spots after crushing No. 14 Ole Miss.
After four top-10 teams lost Saturday, the rankings were rattled and five teams received first-place votes. The Buckeyes received 38 first-place votes, their fewest this season after beginning as the first unanimous preseason No. 1. TCU has five first-place votes, Baylor received 10, Utah has seven and No. 9 Texas A&M has one.
No. 8 Alabama, Texas A&M and No. 10 Oklahoma each gained five spots after impressive victories.
Four teams dropped at least nine spots: Ole Miss, No. 15 Notre Dame, No. 19 Georgia and No. 20 UCLA.
Ohio State was the only team in the top 16 to have the same ranking this week as last.
The Buckeyes held off Indiana 34-27 on Saturday and have now been top-ranked 101 times, matchingOklahoma for the most in the 79-year history of the media poll.
No. 22 Iowa is ranked for the first time since November 2010, No. 24 Toledo is ranked for the first time since November 2012 and No. 25 Boise State is back after falling out last month.
Mississippi State, Wisconsin and West Virginia dropped out of the rankings after losses.
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