With three of the four teams presumably already locked into semifinal spots, the biggest question facing the members of the College Football Playoff selection committee was which team would land in the fourth and final spot when the rankings were revealed Sunday.

After weeks of deliberating it turns out it was Oklahoma all along.

Alabama (13-0) and Clemson (13-0) essentially clinched the top two spots with wins in their respective conference championship games this weekend. The pair held court at the top throughout the six weeks of rankings.

Notre Dame (12-0) remained at the No. 3 spot despite not playing in a conference championship. The Fighting Irish put together an impressive résumé with wins over four ranked teams this season.

But the No. 4 spot has been one of the most heavily debated topics in college football in recent weeks with the committee forced to consider the merits of conference championships vs. a team's overall body of work.

Oklahoma (12-1) won an unprecedented fourth consecutive Big 12 title with an impressive 39-27 win over Texas in the Big 12 Championship Game on Saturday. It was a story of redemption for the Sooners, who were looking for payback against a Longhorns team that handed them their only loss of the season back in October.

Playoff chairman Rob Mullens said the committee spent considerable time discussing the fourth spot but in the end, it came down to the Sooners.

"A one-loss conference champion with their only loss on a neutral field, a close loss to a ranked team that they avenged and their defense has made some big plays the last couple weeks," Mullens said of some of the reasons Oklahoma earned a return trip to the semifinals.

By not adding Georgia, the committee avoided the debate over whether a conference championship is worth more in the eyes of the group or whether a team's overall body of work is better.

Instead, Georgia (11-2) lands at No. 5. The Bulldogs were coming off a heartbreaking loss to top-ranked Alabama in the SEC Championship Game after they squandered a 28-14 lead in the third quarter before eventually losing to the Crimson Tide 35-28.

"Look, I'm not crying over spilled milk," Georgia coach Kirby Smart said. "We had our opportunities in the Alabama game and did not finish and did not take advantage of them. I certainly think we're one of the four best teams in the country, but I also know we're not in the playoffs and we'll have an opportunity to do that next year."

For the second straight season, the Big Ten must watch as it fails to get a team into the playoff. In both years, the league champion was denied a spot in the semifinals by a team that didn't win its conference championship.

No. 6 Ohio State (12-1) clinched its second straight Big Ten title with a 45-24 win over Northwestern on Saturday, but the Buckeyes weren't able to overcome a midseason loss to an unranked Purdue team as well as single-digit wins over Nebraska and Maryland.

This was the sixth and final ranking put out by the 13-member selection committee.

The two semifinals, which rotate yearly, will take place in Miami at the Orange Bowl and in Dallas at the Cotton Bowl on Saturday, Dec. 29.

Alabama will take on Oklahoma in the Orange Bowl while Clemson faces Notre Dame in the Cotton Bowl.

"They're [Oklahoma's offense] a pretty dynamic group," Alabama head coach Nick Saban said. "They've got a lot of weapons. They make a lot of explosive plays. We played against him [Kyler Murray] a little bit when he was at A&M, and he is a very dynamic guy in terms of his athletic ability, his quickness, his ability to make plays with his feet, and he's turned into a really, really efficient passer, who has good skill guys to make good plays to go along with the rest of their weapons."

The remaining New Year's Six games will be hosted by the Fiesta, Peach, Rose and Sugar bowls.

No. 10 Florida will face No. 7 Michigan in the Peach Bowl; No. 8 UCF will face No. 11 LSU in the Fiesta Bowl; No. 9 Washington will face No. 6 Ohio State in the Rose Bowl; and No. 15 Texas will play No. 5 Georgia in the Sugar Bowl.

The CFP National Championship Game will be played on Jan. 7 at Levi's Stadium in Santa Clara, Calif.