With a No. 1 team falling for a fourth consecutive week -- this time it was Kansas at the hands of Oklahoma State -- Indiana (20-2) used its win over Michigan to reclaim the spot on top of the rankings.
The Hoosiers were No. 1 in the pre-season poll and remained there until Dec. 17 when Duke took over after Indiana lost to Butler.
They are back on top after pulling in 25 first-place votes and moving up from the No. 3 spot a week ago. Florida (18-2) receives the other six first-place mentions and is ranked second.
Michigan (20-2) slips only one spot to third while Duke (19-2) is fourth and Kansas (19-2) slips to fifth.
Six teams jump at least four spots this week and three -- Oregon, Wichita State and Mississippi, which all lost twice last week -- fall at least seven places in the poll.
Gonzaga (21-1) comes in sixth this week with Arizona (20-2) in seventh and Michigan State (18-4) eighth. They all move up one spot as Syracuse (18-3) falls three places to ninth. Ohio State (17-4) is voted 10th.
Miami (Fla.) (17-3), unranked two weeks ago, is 11th ahead of Louisville (18-4) at 12th and Creighton (20-3), up four to 13th. Butler (18-4) drops four to 14th and Kansas State (17-4) gains six to 15th.
No. 16 New Mexico (19-3), 17th-ranked Cincinnati (81-4) and No. 18 Minnesota (19-3) all match Kansas State's jump of six places this week. Oregon (18-4), 12th a week ago, comes in 19th and Missouri (16-5) is No. 20.
Georgetown (16-4) returns to the rankings at 21st but Wichita State (19-4) is down eight to 22nd and Mississippi (17-4) drops seven to 23rd. Previously unranked Oklahoma State (15-5) is 24th while Pittsburgh (18-5), also not ranked a week ago, and San Diego State (16-5) are tied for 25th.
North Carolina State and Marquette drop out of the Top 25 this week.
Ohio State has two of this week's key games. The Buckeyes play at Michigan Tuesday and are visited by Indiana Sunday. Also in the Big Ten, Minnesota is at Michigan State Wednesday. In the Big East, Pittsburgh goes to Cincinnati and in the SEC Mississippi is at Missouri. Both of those games are Saturday.