Alex Nieves
Tuesday January 19th, 2016

The 2015–16 college basketball season has been characterized by upsets. Through 12 weeks of the season, 22 different teams have already spent time in the top 10 of the AP poll. Over the last week, four top-five teams suffered a loss. 

The struggles of teams holding the No. 1 spot have been particularly shocking and historic. For the first time since 1949, five No. 1 teams have fallen before February. Oddly, three No. 1 teams have been upset while playing in the state of Iowa. 

Despite its recent loss at Iowa State, Oklahoma remains in the top spot of the AP poll and only time will tell if a No. 1 team can find a way to solidify its place atop the polls as Kentucky did last season. For now, here’s a look at the top-ranked teams that have lost so far this season.

No. 1 North Carolina vs. Northern Iowa - Nov. 21  

The Tar Heels were voted No. 1 in the preseason after returning their top four scorers from last season, when North Carolina's season ended in the Sweet 16. However, Northern Iowa spoiled UNC guard Marcus Paige's homecoming as Paige was sidelined with a hand injury.

The college basketball world didn’t have to wait long for a No. 1 team to suffer a defeat, as North Carolina fell in its fourth game of the season to Northern Iowa. The Tar Heels took a 41–32 lead into the half and cruised to a 16-point advantage with 17:13 left. But momentum shifted and Northern Iowa rattled off a 22–4 run over the next eight minutes to take a 56–54 lead. The Panthers never trailed after that point, holding on for a 71–67 win.

No. 1 Kentucky vs. UCLA - Dec. 3

Coming off of a win over then-No. 5 Duke, Kentucky assumed the top spot in the AP poll in Week 3. The Wildcats were exposed in their first true road game of the season at UCLA's Pauley Pavilion, where they scored the first basket of the game but never led again.  

A year after suffering an embarrassing, 83–44 loss to Kentucky, the Bruins got their revenge, knocking off the top-ranked Wildcats 87–77. The win was the first for UCLA over a No. 1 team since 2003. Kentucky led for all of 31 seconds during the game as John Calipari's team was held to 37.9% shooting. UCLA had five players score in double figures, led by center Thomas Welsh, who posted 21 points and 11 rebounds.

No. 1 Michigan State vs. Iowa - Dec. 29

The Spartans climbed from a No. 13 preseason ranking to No. 1 in Week 5 as do-it-all senior Denzel Valentine quickly established himself as a National Player of the Year candidate as Michigan State defeated Kansas, Providence and Louisville. The Spartans were No. 1 for four weeks until Valentine suffered a knee injury and Michigan State fell on the road against Iowa.

The Spartans held on to the No. 1 rank for longer than any other team this season, topping the polls for four weeks. But Michigan State's reign came to an end at Iowa. The game was the first major contest for the Spartans without star guard Denzel Valentine, and the team struggled in his absence. Michigan State coach Tom Izzo questioned his squad's effort after they never led in the 83–70 loss, telling reporters that Valentine's injury "had nothing to do with the effort you give."

No. 1 Kansas vs. No. 11 West Virginia - Jan. 12

Kansas supplanted the Spartans, who were responsible for the Jayhawks' first loss of the season, atop the polls in Week 9. Bill Self's squad won the Maui Invitational, dismantled Baylor and survived a triple overtime thriller against No. 2 Oklahoma, but a tough game at West Virginia ended the Jayhawks' run.

Eight days after claiming the top spot in the AP poll, the Jayhawks suffered their second loss of the season at the hands of “Press” Virginia. The Mountaineers shot just 33 percent from the field and 3-of-12 from behind the arc but their press defense forced 22 Kansas turnovers—nearly double the Jayhawks’ season average entering the game.

No. 1 Oklahoma vs. No. 19 Iowa State - Jan. 18

The only blemish on Oklahoma's resume through its first 16 games was its 109-106 loss at Allen Fieldhouse, so when the Jayhawks lost a second time, the Sooners claimed the No. 1 spot. But it was only a matter of hours until No. 1 Oklahoma dropped a game on the road.

The Sooners opened conference play with an 87-83 home win over Iowa State on Jan. 2, extending their winning streak to 12 games as Oklahoma gradually climbed the AP poll. In the return game in Ames, Iowa, on Jan. 18, Georges Niang and the Cyclones got revenge against the Sooners. Point guard Monte Morris knocked down the go-ahead jumper and Iowa State made its free throws in the final seconds to dethrone Oklahoma, 82-77, hours after the Sooners were unanimously voted the No. 1 team in the country.

The top–ranked Sooners weren't the only team to lose last week: No. 3 Kansas, No. 4 Villanova and No. 5 Xavier all lost in the week after the Jan. 18 AP poll was released. 

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