Kansas, the nation's only other undefeated Division I men's team, moved up to No. 2 while the Tar Heels dropped to fifth after their loss to Maryland. Drake and Baylor were two new entries to the rankings, joining the Top 25 for the first time in a long time.
Memphis' only other appearance at No. 1 was as short as possible, a one-week stint in 1983.
``We've got one extra day than the last time,'' Memphis coach John Calipari said. ``That team went to No. 1 on a Monday and lost that night. We get to enjoy Monday and Tuesday and until we play at Tulsa on Wednesday night.''
North Carolina was ranked No. 1 in preseason and for the first 10 polls of the regular season. The Tar Heels lost 82-80 to Maryland at home on Saturday and Memphis (17-0) moved up one spot with 49 first-place votes and 1,777 points from the 72-member national media panel.
Kansas (18-0) advanced from third to second with 23 first-place votes and 1,751 points. Tennessee and Duke moved from sixth and seventh to third and fourth. They were followed by North Carolina (18-1).
Drake, which came in at No. 22, is ranked for the first time since the final poll of the 1974-75 season, while No. 25 Baylor was last in the rankings in February 1969.
Although this is Memphis' first No. 1 ranking since that 64-56 loss at Virginia Tech on Jan. 10, 1983, Calipari had his teams at Massachusetts there for a total of 14 weeks over the 1994-95 and 1995-96 seasons.
``My 1995 team had the same camaraderie and synergy this team has but this team has it with more guys because we'll play 10, 11 guys where that UMass team was basically five guys,'' Calipari said. ``It'll matter to these guys. I've coached at UMass and here and at those kind of places, non-BCS schools, most of those guys were not silver-spooned not McDonald's All-Americans and they take pride in it because it's a notch in their belt to be able to say `You guys didn't think I was that good.''
Calipari was honest that there is a bigger target for him than being No. 1.
``For me as a coach the only rating I worry about is April 7,'' he said, referring to the date of the national championship game. ``If you said to me I could have the No. 1 ranking or a No. 1 seeding, I'd take the seeding every time. For your players and the school, though, this is huge.''
This week's poll is the first major shuffling of the season as 15 ranked teams lost a game last week and three of those _ Texas A&M, Marquette and Miami _ lost twice.
Washington State moved up two spots to sixth and was followed by Indiana, UCLA, Georgetown and Michigan State.
Wisconsin was 11th followed by Texas, Pittsburgh, Vanderbilt, Butler, Dayton, Mississippi, Texas A&M, Villanova and Stanford, the week's third newcomer.
The last five ranked teams were Marquette, Drake, Xavier, Arizona State and Baylor.
Drake (16-1) moved into the poll on a 15-game winning streak with the only loss to Saint Mary's, Calif., in the second game of the season.
``For a team that lost five seniors and four starters from last year and that was ranked ninth in the Missouri Valley Conference preseason poll, we felt, our team and coaches, and probably our fans, felt we could have a pretty good team this year and be better than people expected but this wasn't what people were thinking, a national ranking,'' said first-year coach Keno Davis, who succeeded his father, Tom.
Baylor (15-2) lost to Washington State and Arkansas this season and has opened the Big 12 with three straight wins.
But the Bears have completed an impressive comeback under fifth-year coach Scott Drew, who took over after former coach Dave Bliss resigned following a scandal sparked by the slaying of former player Patrick Dennehy by a teammate. NCAA penalties for wrongdoing uncovered during Bliss' tenure forced the program to deal with depleted rosters and limited schedules.
Baylor is ranked for the first time in almost 40 years and for just the third time in school history with the other in the first season the AP conducted a poll, 1948-49.
``This is well-deserved for the players for what they've done on the court this year,'' Drew said. ``We are so pleased after all the lean years and not being ranked since 1969, it's a great tribute to them. It will be very tough to get the smiles off their faces today.''
Stanford (15-3) moved into the rankings for the third time this season coming off a home sweep of Arizona and Arizona State.
Miami (14-3) dropped out from 21st after losses last week to Boston College and North Carolina State. Rhode Island (15-3) fell out from 23rd after last week's loss to Saint Louis. Clemson (14-4), which was ranked as high as 15th this season, dropped out from No. 24 after losing to Duke on Saturday.