A few things to watch the first Saturday of October, when for the first time this season all 10 teams play on the same day - and against each other in five conference matchups:
GAME OF THE WEEK: No. 4 Oklahoma at No. 25 TCU. The Big 12 will be down to no more than two undefeated teams after this game, when the Horned Frogs are the last team to play their Big 12 opener. (No. 7 Baylor, the league's only other undefeated team, plays at Texas at the same time Saturday). While the Sooners have won both series games since TCU joined the Big 12, those two victories were by a combined 10 points. Oklahoma had a 76-yard TD run in the fourth quarter of last year's 20-17 win at home, and two years ago clinched a share of the Big 12 title with a regular season-ending 24-17 win at TCU, which had fourth-down incompletion in the end zone in the final minute. The Horned Frogs changed their offense this season to be more like other Big 12 teams. Their 44.7 points and 532 total yards a game are on par with Oklahoma's 44.8 points and 495 yards.
BEST MATCHUP: Baylor's offensive line, which hasn't allowed a sack this season, against the Texas defense that has 17 sacks by 12 different players. ''They're going to have a good week,'' Baylor quarterback Bryce Petty said of his linemen. ''I'm excited to see the challenge that they're about to face.'' The Longhorns have gotten 12 of those sacks from defensive tackles or ends. Texas is second in the Big 12 with its 17 sacks, one behind Baylor.
INSIDE THE NUMBERS: Oklahoma State, which hosts Iowa State this week, has won 13 of its last 15 conference games at home. ... Seven Big 12 quarterbacks are ranked among the nation's top 36 in total defense. ... Texas Tech had 16 penalties for 158 yards last week. The Red Raiders, who play at Kansas State, are the league's most-penalized team with 46 flags for 422 yards, an average of 105.5 yards per game.
LONG SHOT: Kansas plays its first game since coach Charlie Weis was fired, and is a more than three-touchdown underdog at West Virginia for defensive coordinator Clint Bowen's first game as interim coach. Weis' only conference victory for the Jayhawks was 31-19 at home against the Mountaineers last year, but Kansas lost 59-10 in Morgantown two years ago. West Virginia's losses were tight games against No. 3 Alabama and No. 4 Oklahoma.
IMPACT PLAYER: Oklahoma State junior QB Daxx Garman completed 17 of 31 passes for 370 yards and four TDs in a win over Texas Tech. He had six completions of at least 30 yards, four of those for at least 40 yards. Garman has 685 yards passing and six TDs in his two starts replacing injured J.W. Walsh.
Compiled by AP Sports Writer Stephen Hawkins in Fort Worth, Texas.
Follow Stephen Hawkins on Twitter at https://twitter.com/hawkaptexas