Clemson, Oklahoma and Georgia took over the business in their respective conference championship games on Saturday and received places on Sunday in the College Football Heat.
Alabama was selected as the fourth team, over Ohio State.
The No. 1 Tigers will face the No. 4 Crimson Tide in the Allstate Sugar Bowl, and the No. 2 Sooners will play the No. 3 Bulldogs in the Rose Bowl Game Presented by Northwestern Mutual on January 1, as announced on Sunday the CFP selection committee.
Alabama opened as a 1-point favorite over Clemson, and Oklahoma opened as a 3-point favorite over Georgia at the Westgate Las Vegas SuperBook.
The winners of the semifinal will play for the national title in January. 8 in Atlanta.
It's the third consecutive season that Alabama and Clemson will meet in the playoffs, although this time in the semifinals. The Tide beat the Tigers in a clbadic national championship game in Glendale, Arizona, two seasons ago. The teams played another thriller last season and Clemson took the title in Tampa, Florida.
Alabama (11-1) made the cut despite being inactive on Saturday and not winning the SEC title. His only loss was a 26-14 against Auburn in the Iron Bowl on November 25.
The Buckeyes (11-2) resisted to beat Wisconsin 27-21 in the Big Ten championship game, but they had a 31- CFP committee chairman Kirby Hocutt said the loss of Iowa weighed on the state of Ohio and that the Buckeyes were not close enough to the result of the Tide for the Big Ten Championship to matter.
"They saw Alabama playing week after week, the selection committee believed that Alabama was the best football team," said Hocutt. "When we looked at Ohio State, when you looked at your resume it was impressive, but it was not enough for the selection committee to place them above Alabama."
When choosing Alabama for Ohio State for No. 4, the selection committee had to consider the Tide "unequivocally" better, which allows them to throw the tiebreak criteria to the same scenario that allowed the Buckeyes to enter last year without winni ng to their division and despite a defeat face to face with Penn State .
Alabama is the only team that has appeared in every playoff since they started in 2014.
Ohio State finished in No. 5 and Wisconsin No. 6.
After a 38-3 win over Miami , defending national champion Clemson (12-1) has now won three consecutive ACC titles and secured the No. 1 spot in the playoff standings for the second time in three years. .
Oklahoma (12-1) overcame a stunning loss to the state of Iowa in October to win its third consecutive Big 12 title with a convincing 41-17 victory over TCU.
Georgia (12-1) defeated Auburn 28-7 in the SEC championship game, avenging its only loss of the season: an ugly 40-17 defeat at Auburn three weeks ago in which it was completely dominated on both sides of the ball.
Georgia and Oklahoma never played. The Bulldogs have increased in their second season with coach Kirby Smart. After winning eight games last season, Georgia won the SEC for the first time since 2005.
Oklahoma is in the playoffs for the second time and is likely to bring the winner of the Heisman Trophy. Quarterback Baker Mayfield is the favorite to win the prize next weekend. If so, Mayfield will be the third player to go from winning the Heisman to the tiebreaker, joining Marcus Mariota of Oregon in 2014 and Derrick Henry of Alabama in 2015.
This report used information from The Associated Press .