By Ralph D. Russo

AP College Football Writer

Ohio State jumped LSU to No. 1 in the College Football Playoff rankings with two weeks left to go before selection Sunday.

LSU slipped to second Tuesday night and Clemson remained third while Georgia held on at four. If playoff history holds form, three of those top four teams will reach the semifinals.

Alabama remained No. 5 in the selection committee’s third rankings, with Utah moving up a spot to No. 6. The Utes are the only Pac-12 team in the top 10 after Oregon dropped eight spots to 14th.

Oklahoma is seventh followed by Minnesota, Baylor and Penn State.

In each of the first five years of the playoff, three of the top four teams in the rankings heading into rivalry weekend reached the semifinals, including the No. 1 team every time.

Now that spot belongs to Ohio State, which committee chairman Ron Mullens has continual referred to as a complete team.

“Competing consistently and really highly ranked on offense and defense. Performing at a high level on both,” committee chairman Rob Mullens said of Ohio State, which currently leads the nation in scoring and points allowed.

The Buckeyes beat Penn State last week 28-17, its third victory of the season against team currently ranked along with No. 12 Wisconsin and No. 18 Cincinnati. LSU has beaten No. 5 Alabama, No. 11 Florida and No. 15 Auburn.

Memphis is 17th, remaining the highest ranked team from the Group of Five conferences. The highest ranked conference champion from outside the Power Five is guaranteed a spot in the New Year’s Six bowls. This year that would be the Cotton Bowl. Memphis and Cincinnati play this week and could meet the next week in the American Athletic Conference championship game. Boise State from the Mountain West is 20th.

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DOWN THE STRETCH THEY COME

There are some signs that the stretch run this season could be more volatile than in past playoff years. First off, three times in the previous five years one of the teams that was ranked in the top four heading into rivalry weekend and made the playoff only played one more game.

In 2015, Oklahoma reached the CFP as the Big 12 champion, but the conference had no title game so the Sooners were able to kick back with their 11-1 record after beating rival Oklahoma State. The Sooners did slip from third to fourth in the final rankings.

In 2016, Ohio State was shut out of the Big Ten championship game because of a loss to Penn State, but the committee liked the Buckeyes 11-1 record with three victories against top-10 teams. They made the field, but also dropped a spot from second to third.

Last year Notre Dame, a football independent, was No. 3 when it wrapped up its perfect regular season on rivalry weekend and stayed that way on selection Sunday.

In 2017, Alabama lost on rivalry weekend to Auburn as No. 1 in the CFP rankings. That eliminated the 11-1 Tide from the SEC championship game and dropped it to No. 5 in the second-to-last CFP rankings. Alabama moved back to four after sitting out championship weekend when No. 4 and unbeaten Wisconsin lost the Big Ten championship game to an Ohio State team with two losses.

This season, all the teams in the top four have two more games left, including an SEC championship game that will match LSU and Georgia. The Tigers also face Texas A&M this weekend and the Bulldogs face rival Georgia Tech

Ohio State has two more ranked foes to face before selection Sunday in No. 13 Michigan in Saturday and either Wisconsin or Minnesota in the Big Ten championship.

Clemson has the smoothest path to the playoff with struggling South Carolina this week and an ACC championship game against either No. 24 Virginia Tech or Virginia.

Heading down the stretch there are nine teams with a realistic chance of making the playoff. The top four simply need to win out. In fact, undefeated LSU and Ohio State might even have some leeway to lose one of their final two. Unbeaten Clemson might not get that kind of slack, but you could argue if Georgia can make the playoff with a loss to South Carolina and a conference championship, why can’t the Tigers?

The other contenders and what they need to happen over the next two weeks:

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ALABAMA

— Beat the stuffing out of Auburn on the road with backup quarterback Mac Jones.

— LSU wins out.

— Hope having the best loss outweighs a light resume and no conference title.

— Some cannibalization in the Big 12 and Pac-12 over the next two weeks would also help — a lot.

UTAH

— Win out in impressive fashion.

— LSU and Ohio State win out and eliminate other contenders in their conferences.

— Hope the Pac-12 title gives it an edge over a Tua-less Alabama.

— Hope a pile of blow-out victories is more impressive to the committee than the close calls the Big 12 champion will have.

OKLAHOMA AND BAYLOR

— Similar to Utah in that either potential Big 12 champ could use the SEC and Big Ten favorites to take care of business.

— A slip up by Utah (or Alabama) could come in handy.

MINNESOTA

— The Gophers probably just need to win out and slap down a resume in front of the committee that includes a Big Ten championship with victories against Penn State, Wisconsin and Ohio State.

— It probably wouldn’t hurt if LSU cleared out Georgia, too. There is a two Big Ten-team playoff in play here with Ohio State.

Among the teams that have already lost twice, Wisconsin is the best long shot if it can beat Minnesota and avenge an earlier loss to the Buckeyes in the Big Ten title game.

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MORE SURGERY FOR MINNESOTA FOOTBALL PLAYER, CANCER SURVIVOR

MINNEAPOLIS (AP) — University of Minnesota football player and four-time cancer survivor Casey O’Brien is facing more surgery this week to remove a spot in a lung.

The walk-on holder made his college debut at Rutgers on Oct. 19, holding all three of the Gophers’ fourth-quarter extra points in their 42-7 victory.

O’Brien this season has shared the story of his cancer fight with ESPN’s “College GameDay” and other programs.

The sophomore from St. Paul, Minnesota, initially was diagnosed with a rare bone cancer at age 13. He has since had a left knee replacement, multiple lung operations and chemotherapy treatments.

The Star Tribune reports O’Brien was nearly two years cancer-free when he wrote about the surgery update Monday on Twitter.

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Information from: Star Tribune, http://www.startribune.com