Can any team maintain the nation's No. 1 rank?

Iowa stuns No.1 Michigan State (1:06)

SportsCenter Highlight of the Night: Iowa hands Michigan State its first loss of the season, beating the Spartans 83-70. (1:06)

Early in the second half, as Michigan State tried desperately to claw its way back from a double-digit deficit at Iowa, Spartans guard Alvin Ellis deflected the ball into the Hawkeyes' basket.

It was that kind of night for the soon-to-be former No. 1-ranked team in the nation, which lost to Iowa 83-70 Tuesday night.

The way this season is going, there will be many more upsets like this, regardless of what school is holding the paper crown. Welcome to the revolving door of No. 1-ranked teams.

Consider this: In the previous five seasons, The Associated Press Top 25 poll has never had four different teams ranked No. 1 within the first nine weeks. Last season (Kentucky) and during the 2010-11 season (Duke), only one team held the top billing for that entire stretch.

Next week will be the ninth week of the poll, and it will be the fourth different top-ranked team.

For one last time, all together with feeling: There are no great teams in college basketball, only a lot of very good ones.

So it's very likely the trend of losses at No. 1 will continue to play out the same way it did for Michigan State, North Carolina and Kentucky, which each played road games as a No. 1 only to return home knowing they'd just lost the honor.

The Spartans and Tar Heels were similar in that an untimely injury contributed to their respective losses. Michigan State has no one who can fill the void left by Denzel Valentine, just like Carolina did not have anyone to take the place of Marcus Paige. But to be clear, great teams have the depth to overcome those kinds of temporary absences. This season, the there's a thin line between good and great.

No. 2 Kansas, fresh off its 78-53 shellacking of UC Irvine Tuesday night, is now poised to be crowned the new No. 1 team on Monday. (Of course, that's provided the Jayhawks can get past No. 23 Baylor on Saturday.)

Even if they do, No. 3 Oklahoma awaits the Jayhawks next Monday for an early Big 12 showdown of potential league champions. Should the Sooners come away from Allen Fieldhouse with a win, that would literally mean the No. 1 ranking only held true for roughly 12 hours.

Like things could get that crazy.

Matter of fact, let's go ahead and scratch every Big 12 team now from holding the crown too long. The league is just too deep. Should the Sooners elevate up to No. 1, No. 11 Iowa State is hovering just outside the top 10, ready to pounce.

If any team can make it through that league -- where every team plays home and road games against the entire league -- they'd certainly deserve to be ranked No. 1 and they'd deserve to be the No. 1 overall seed in the NCAA tournament.

But don't expect that to happen.

So what about No. 4 Maryland? The Terrapins topped the ESPN.com Power Rankings in the preseason. They'll get a bit of a break in an unbalanced Big Ten schedule that has them only facing Michigan State and Indiana once.

A number of close calls against Georgetown, Rider and Illinois State early in the season showed the Terps had flaws. They're just as likely to lose their first league road game at Northwestern as they are to win at Michigan State or Indiana. They just haven't yet proved to be trustworthy.

Can't blame Maryland; every team near the top has it's drawbacks.

No. 5 Virginia? It might be overly reliant on Malcolm Brogdon in the same way Michigan State is with Valentine.

No. 6 Xavier? It might not be able to handle the circus that would come on that campus and the city of Cincinnati by being No. 1.

No. 7 North Carolina? Even with a second chance, the Heels still might not have figured out how to close out teams.

No. 8 Arizona? It's still turning the ball over at too high a rate to take seriously as a long-term solution at No. 1.

No. 9 Butler? It might be too small to continually outplay teams with some size.

No. 10 Kentucky? With inconsistent post play, it likely can't survive a poor shooting from the perimeter without another loss.

And, of course, Michigan State could rise back to No. 1, especially when Valentine returns healthy. One thing his absence has shown is how vulnerable the Spartans are without him. So that means even if he's in the lineup, he's just an off-shooting night away from the Spartans losing.

There's no need to continue.

They all have flaws that just have to be accepted and embraced. Just like the revolving door at No. 1.