CFP top five unchanged, but Big Ten title game will be a fight for No. 4

With the top five teams in this week's College Football Playoff rankings remaining the same from a week ago, Saturday's slate of conference championship games will play a large part in determining who will have a shot at the national title.

The biggest matchup this week will be the Big Ten title game, which will pit No. 4 Iowaagainst No. 5 Michigan State,with the winner likely securing a spot in the four-team playoff. The Hawkeyes (12-0) completed the program's first undefeated regular season in 93 years, while the Spartans pummeled Penn State for their third straight victory.

Clemsonand Alabama, Nos. 1 and 2, respectively, also face CFP-ranked foes in their conference title games.

"The committee debated long and hard about the No. 1 and No. 2 teams," College Football Playoff committee chairman Jeff Long said.

The Tigers will seek to win the ACC when they face No. 10 North Carolinaon Saturday night. The Tar Heels, winners of 11 straight, moved up four spots and have a chance to dash the national title hopes of Dabo Swinney's team, which has been the top squad in each week's CFP rankings this season.

Alabama, the lone SEC team with a shot at the national title, will face a Floridasquad that took another stumble this week. The Gators fell six slots to No. 18 after a woeful performance against in-state rivalFlorida State. The Seminoles rode their 27-2 victoryto a No. 9 ranking this week.

While four of the top five teams will sweat out a conference title game this week, No. 3 Oklahomawill sit idle as the Big 12 continues to operate without a championship game. The Sooners made one final impression on the CFP committee with a 58-23 rout of Oklahoma State(No. 17) on Saturday.

Defending champion Ohio Stateoccupies the No. 6 spot. The Buckeyes moved up two places after drubbing rival Michigan. The loss dropped the Wolverines from No. 10 to No. 15. Ohio State could get a chance to defend its championship if Clemson or Alabama get tripped up in their conference title games. The four semifinalists and final CFP rankings will be revealed at 12 p.m. ET Sunday on College Football Selection Day on ESPN.

At No. 7,Stanfordis the only Pac-12 team in the top 10. The Cardinal will face No. 20 USCin the conference championship game Saturday.Notre Dame, which lost a heartbreaker to Stanford last week, checks in at No. 8.

Two teams from the Big 12 sit just outside the top 10, as TCUand Baylorslide in at Nos. 11 and 12, respectively. Ole Miss, Northwesternand Michigan round out the top 15. Checking in behind the Big Ten duo are Oregon, Oklahoma State and Florida.

At. No. 19, Houstonis the highest team from a Group of 5 conference. The Cougars rolled past Navy(No. 23) and will face No. 22 Templein the AAC championship game.

After a one-week hiatus, USC returns to the CFP rankings at No. 20, fresh off a victory over crosstown rival UCLA. The Trojans hope to ride the news of Clay Helton's being named the team's permanent coach to a Pac-12 title on Saturday.

Another coach who went into last week with an uncertain status is Les Miles, whose LSU Tigers are No. 21 after spending a week outside of the poll. The Tigers are followed by Temple, Navy, Utahand Tennessee.