The penultimate College Football Playoff rankings, released Tuesday evening, strongly reflected the continuing re-emergence of the Big Ten. Obscured and peeved earlier this century while the Southeastern Conference won seven straight national titles, the Big Ten holds down half of the top six spots and all three of the positions (4-5-6) considered most intriguing.

The top five remained unchanged from last week — No. 1 Clemson, No. 2 Alabama, No. 3 Oklahoma, No. 4 Iowa and No. 5 Michigan State — while Ohio State, at No. 6, became the highest-ranked team among those who will need help from others come Saturday.

Iowa (12-0) will play Michigan State (11-1) in the Big Ten championship game Saturday evening in Indianapolis, with the winner presumed bound for the sport’s second four-team playoff, a quartet that will become known upon the release of the final rankings on Sunday at 12:30 p.m. While either Iowa or Michigan State will lose, idle Ohio State (11-1) must hope another team from above also will lose — either Clemson, which plays No. 10 North Carolina (11-1) in the ACC championship game, or Alabama, which plays No. 18 Florida (10-2) in the SEC championship game.

Ohio State, the defending national champions, must hope also that No. 7 Stanford (10-2) does not vault past it, given that the Cardinal has a chance to pad its résumé with a Pacific-12 championship game against No. 20 Southern California (8-4), which Stanford beat already this season on Sept. 19 in Los Angeles.

On the subject of whether the two-season-old playoff ultimately could see its first conference non-champion as a playoff entry, selection committee chairman Jeff Long said: “I don’t know how to answer that because I don’t know any of the variables of that non-champion. It depends on how the other teams play and what the results are above and below them.”

There will be no result from above that Oklahoma (11-1), which has finished its regular season, because the Big 12 does not stage a conference championship game. That fact hindered the league last year when two of its contenders, Baylor and TCU, watched Ohio State leapfrog them to the coveted No. 4 spot on the steam of a 59-0 win over Wisconsin in the Big Ten championship game on the eve of the final rankings.

If Ohio State somehow were to reach the playoff again, that would cast the Big Ten in an even larger new light as the first league to snare two spots in a single season.

“Protocol clearly says there can be more than one team from a conference in the final four,” Long said, “so that’s definitely a possibility.”

While Long told of vigorous debates in the committee room over Clemson or Alabama for No. 1 — Clemson has held it for all five weeks of the rankings — and over Iowa or Michigan State for No. 4, he did not note the same doubt around Oklahoma at No. 3 and cited the Sooners’ four wins over current top 25 teams.

“A conference championship game, not having one or having one can help or hurt you, depending on the circumstances of that particular season,” Long said.

Having one is North Carolina’s only shot at the top four, and that shot would appear to be long. After scoring their 11th straight win, the Tar Heels rose to No. 10, just behind three teams with inferior records: Stanford (10-2), No. 8 Notre Dame (10-2) and No. 9 Florida State (10-2). That reflects the Tar Heels’ disrespected schedule with its whopping two teams from the Football Championship Subdivision, North Carolina A&T and Delaware. That also mandates a dual requirement: that the Tar Heels win impressively over Clemson and that they make a gigantic leap in the rankings.

While the committee gave a debut ranking to No. 25 Tennessee (8-4), which would seem to help Oklahoma’s cause because Oklahoma won at Tennessee, it kept a strong respect for the American Athletic Conference.

Even after a 52-31 loss at Houston, Navy (9-2) remained ranked, sliding from No. 15 to No. 23, as Houston (11-1) took over No. 19, ahead of its conference championship game set for Saturday in Houston against No. 22 Temple (10-2). The winner of that should have a considerable shot at the New Year’s bowl bid allotted the Group of Five, which is the tier of conferences deemed just below the Power Five.