It was nearing midnight when the members of the College Football Playoff selection committee finally sat down to begin deliberations.
Clemson, Oklahoma and Georgia were obvious choices for the first three spots in their bracket, but the fourth and final slot wasn't going to be as easy to fill.
"We walked into that meeting room, I think, knowing that we had a big task in front of us," committee chairman Kirby Hocutt said. "We had a very important conversation."
The decision to invite Alabama instead of Ohio State was based on both definable metrics and something more subjective, something not explicitly listed in the CFP protocol.
As Hocutt put it: "How you play in the wins matters, how you play in the losses matters."
So the most controversial call of this college season came down to an embarrassing stumble that Ohio State suffered weeks earlier, when the Buckeyes fell by 31 points to unranked Iowa.
Hocutt defined that result as "damaging" and Ohio State coach Urban Meyer did not put up much of an argument.
"We had a bad loss. That happened," Meyer said. "So move on."
The Buckeyes weren't the only ones to pay this price. It seems USC could not overcome a 49-14 flop at Notre Dame in late October.
Though the Trojans finished strong, defeating Stanford for the Pac-12 Conference title Friday night, they ended up at No. 8 and will play, appropriately enough, Ohio State in the Cotton Bowl.
"You put your best resume out there, and then the committee chooses who they're going to select in those spots," USC coach Clay Helton said. "It's a hard job for them."
The CFP's printed list of criteria includes strength of schedule, outcomes against common opponents and conference championships.
But the protocol also stresses "flexibility and discretion" to move beyond mathematical formulas in identifying the four best teams in the nation. As the CFP website states: "Ranking football teams is an art, not a science."
So the choice between Alabama and Ohio State would involve a wide-ranging discussion that continued past 2 a.m. on Sunday and resumed later in the morning.
Three of the 13 voting members — Clemson athletic director Dan Radakovich, Ohio State athletic director Gene Smith and Frank Beamer, whose son coaches at Georgia — were recused because of their associations with the teams involved.
"It keeps the process above reproach," CFP executive director Bill Hancock said.
The Buckeyes had a 15-point loss to Oklahoma and that more-lopsided defeat in Iowa as part of their 11-2 record, but had rebounded to defeat No. 6 Wisconsin for the Big Ten Conference championship Saturday night.
"We were feeling good," linebacker Chris Worley said.
Alabama had a noticeable hole in its resume, failing to qualify for the Southeastern Conference title game.
Fourteen of the 16 playoff teams in the short history of the CFP have been conference champions. But the Crimson Tide had an 11-1 record, their loss coming on the road against highly ranked Auburn.
Other factors weighed in their favor.
All season, they had hovered at or near the top of the polls. Hocutt said the committee noted that Alabama ranked above Ohio State in key statistical categories.
"We challenged ourselves and played the devil's advocate to make sure we thought through this from every direction," he said.
The committee leaned toward Alabama's "full body of work" during that first session and later confirmed it.
There was precedent for their reasoning. Last season, Ohio State was a one-loss team that failed to win its conference when it was picked instead of Big Ten champion Penn State.
There was also something new about this season's final ranking.
For the first time, the playoffs will include two teams from the same conference and exclude the Big Ten and Pac-12.
That might rile some people but it is hard to argue the entertainment value of the resulting semifinals.
The Sugar Bowl gets a rematch of last season's championship game in which Clemson defeated Alabama in the final seconds.
The Rose Bowl features Oklahoma quarterback Baker Mayfield, the presumed Heisman Trophy winner, against a Georgia team that ranks fourth nationally in yards given up.
"Obviously, they're really good defensively," Oklahoma coach Lincoln Riley said. "Doesn't take time to figure that out."
The CFP is also responsible for pairings in the major bowl games and set the traditional USC-Ohio State matchup in a nontraditional setting Dec. 29.
The Peach Bowl could be interesting, too, with No. 7 Auburn facing No. 12 Central Florida, this season's Cinderella team from the smaller Group of Five conferences.
But in the coming days, the conversation will probably linger on Alabama and Ohio State. If the CFP has flexibility and discretion, so do its critics.
Controversy isn't new to the college playoffs. Hocutt said the committee is comfortable with its decision.
"We know how important it is to get it right," he said. "And that's what we did."
Final College Football Playoff rankings:
5. Ohio State
9. Penn State
12. Central Florida
14. Notre Dame
15. Texas Christian
16. Michigan State
17. Louisiana State
18. Washington State
19. Oklahoma State
22. Virginia Tech
23. Mississippi State
24. North Carolina State
25. Boise State
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5:05 p.m.: This article was updated.
12:20 p.m.: This article was updated with the final rankings.
11:05 a.m.: This article was updated with USC's final ranking.
10:15 a.m.: This article was updated with information about the semifinal games and national championship.