AP College Basketball Poll 2015: Complete Week 4 Rankings Released

On Saturday, Michigan State's football team guaranteed itself a chance at a national championship. Two days later, its basketball team reached the sport's regular-season pinnacle. 

Tom Izzo's Spartans ascended to the nation's top spot in the latest Associated Press poll, ascending past Kentucky and Maryland, which each lost last week. Kansas moves up to the second spot, while North Carolina, Iowa State and Kentucky comprise the remainder of the Top Five.

Here's a look at how the full rankings played out:

Ranking	Team
1	Michigan State
2	Kansas
3	North Carolina
4	Iowa State
5	Kentucky
6	Maryland
7	Oklahoma
8	Duke
9	Villanova
10	Virginia
11	Purdue
12	Xavier
13	Arizona
14	West Virginia
15	Providence
16	Baylor
17	Miami (Fla.)
18	Butler
19	SMU
20	Gonzaga
21	Vanderbilt
22	Louisville
23	Cincinnati
24	Oregon
25	Utah

The biggest changes are at the top, as John Calipari's Wildcats dropped to No. 5 after taking their first loss. Thomas Welsh scored 21 points, and all five UCLA starters were in double figures as the Bruins shocked the nation with an 87-77 win Thursday night. Kentucky's formerly formidable defense allowed 50 second-half points, and Jamal Murray and Tyler Ulis combined to shoot 7-of-28 from the field.

"We have to understand: They play tougher, they play rougher, they play more focused," Calipari said, per Alex Forkner of 247Sports. "That’s what it is. Playing at Kentucky, that’s what you get. We get that other team’s best. We walk into an arena, it’s their best crowd in a while. That’s what it is. It’s Kentucky."

Jay Bilas of ESPN noted UCLA's dominant performance:

A day earlier, the team most likely to take over for Kentucky was also sent packing. Marcus Paige scored 20 points in his return to the floor, leading North Carolina to an 89-81 win over second-ranked Maryland. Paige sat out the season's first six games due to a broken hand but did not miss a beat, knocking down four of five three-pointers and adding five assists.

"He's like coach's right-hand man," forward Brice Johnson said, per C.L. Brown of ESPN.com. "Coach talks to him the most, and he knows everything that we need to do. He's our floor general, he's our leader. He knows what he's talking about when he tells us to do things."

Defensive breakdowns were largely at the center of things for the Terrapins, who were making their first trip away from home. Melo Trimble poured in 23 points and 12 assists, Rasheed Sulaimon had 18, and Robert Carter had 11, but the Terps allowed North Carolina to shoot 53.2 percent from the floor. After close calls against Georgetown and Rider, it's fair to wonder if Maryland needs to do significant work to re-emerge as a title contender.

Nevertheless, the struggles of the top two opened the door for Michigan State. Izzo's team moves to No. 1 five days after taking down Louisville in the ACC/Big Ten Challenge. The Spartans scored 42 second-half points to win a game in which they trailed for the first 29-plus minutes. Denzel Valentine's 25 points, seven assists and five rebounds led the way, while Bryn Forbes added 20 points.

"That's exciting," Forbes said of being ranked No. 1, per Matt Wenzel of MLive.com. "It's always exciting to be ranked as the best team in college basketball. I think we've got a bigger goal in mind than just to be ranked No. 1. A national championship is what we're striving for."

Looking down the list, two teams dropped out of the rankings after disappointing weeks. Syracuse dropped back-to-back contests against Wisconsin and Georgetown after a 6-0 start, while Texas A&M lost its second in three tries against Arizona State. 

They were replaced by No. 18 Butler and No. 25 Utah. Butler upset Cincinnati on the road last week and looks fully recovered from its early-season loss to Miami. Utah has reeled off four straight since its own loss to the Hurricanes. 

Follow Tyler Conway (@tylerconway22) on Twitter.