The initial College Football Playoff rankings were released this week, with Alabama, Clemson, LSU and Notre Dame holding down the top four spots.
The playoff picture could change drastically the first post-rankings weekend.
The schedule is full of huge games, including top-ranked Alabama at LSU, No. 5 Michigan against No. 14 Penn State and No. 6 Georgia at No. 11 Kentucky.
It's about to get real interesting in a hurry.
Here's a rundown of some things to know heading into the season's 10th weekend:
No. 1 Alabama (8-0, 5-0 SEC) at No. 4 LSU (7-1, 4-1)
This isn't just the biggest game of the week, it could be the biggest of the season so far.
The champion Crimson Tide have yet to be challenged in defense of their national title, winning their first eight games by an average of nearly 40 points.
That could change this week in Baton Rouge.
LSU leads the nation with 14 interceptions and is fifth in pass defense efficiency, so the Tigers may have the right components to at least slow Tua Tagovailoa and the nation's top-scoring offense.
Regardless how it plays out, this is a must-watch game.
Tagovailoa has been the front-runner to win the Heisman Trophy, but don't count out Kyler Murray. The Oklahoma quarterback took advantage of Alabama's bye week to grab some of the spotlight, throwing for 353 yards and accounting for four touchdowns in the No. 7 Sooners' blowout win over Kansas State.
Murray and Oklahoma face Texas Tech on Saturday, which could help pad his numbers. He could use some help from LSU's defense, too; shut down Tagovailoa and Alabama's offense, the Tigers could boost Murray's Heisman bid.
Of course, if Tagovailoa has a big game or signature moment against LSU, the race could all but be over.
NUMBERS TO KNOW
2_Average number of teams from the initial CFP rankings that go on to make the playoffs.
13.0_Points per game allowed by Clemson and Kentucky, best in the FBS
16_Seed of Ohio State in the initial 2014 rankings, the lowest to reach the playoffs. The Buckeyes are No. 10 this year.
144.4_Average yards rushing per game by Wisconsin's Jonathan Taylor, leading the nation. The Badgers play Saturday against Rutgers, which is 115th in the FBS against the run, allowing 224 yards per game.
UNDER THE RADAR
No. 14 Penn State at No. 5 Michigan.
The Wolverines (7-1, 5-0) are in a good position in the CFP playoff at No. 5 with two of the teams ahead of them playing each other. Michigan also is in position to win the Big Ten title for the first time since 2004.
A big test comes this weekend, though.
The Nittany Lions (6-2, 3-2) are No. 14 in the CFP and need a win badly to remain in contention for the Big Ten title. Penn State's two losses were by a combined five points and is one of the nation's highest-scoring teams with 41 per game.
Michigan has the nation's top defense and is coming off a bye after a seven-game winning streak.
If it were not for the Alabama-LSU game, this would have been the game of the week.
HOT SEAT WATCH
Chris Ash, Rutgers.
A $9.8 million buyout might be the only reason Ash is still at Rutgers.
The Scarlet Knights are 1-7 and 0-4 in the Big Ten, their only win coming against Texas State in the season opener. Rutgers has losses to Kansas and Buffalo this season, and Ash is 7-25 in three seasons as coach.
Scarlet Knights fans have been calling for his firing, but the buyout might prohibit the move for an athletic department that may not be able to afford it.
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