Halfway through the final season of the Big 12 as we know it, there are only three undefeated teams left — and that will be reduced by next weekend, maybe to only one.
The unblemished trio is Oklahoma, Oklahoma State and Missouri, all 6-0 overall and still with some head-to-head games remaining. They are also the only teams without a loss in the Big 12, though only Texas Tech has played more than three conference games so far.
Oklahoma, No. 1 in the first BCS standings, plays at Missouri in a prime-time game Saturday night. They are meeting for the first time since the 2008 Big 12 championship game after also being the 2007 title game matchup. The Sooners won both handily.
“Our players are very well aware of No. 1, how good Oklahoma is, and No. 2, how it’s such a big game,” Missouri coach Gary Pinkel said Monday on the Big 12 coaches conference call. “Talking about that will not help us play any better.”
Nebraska (5-1, 1-1 Big 12), the preseason North Division favorite, has already seen the end of its chance to have a spotless farewell. The Cornhuskers play at undefeated Oklahoma State on Saturday.
Colorado (3-3, 0-2), which along with Nebraska is leaving the Big 12 after this season, is coming off a home loss to Baylor (5-2, 2-1) — which has more wins than Texas (4-2, 2-1).
The Bears need only one more win to be bowl eligible for the first time in the league’s 15 seasons.
With seven weeks down and seven weeks to go until the last Big 12 championship game Dec. 5 at Cowboys Stadium — and the league being reduced to 10 teams — here’s a look at some things that have happened and questions still to be answered:

    • THE UNDEFEATED Os: Quality victories over Florida State, Air Force and Texas helped push Oklahoma to the top of the BCS standings. Yet, the Sooners, third in the AP poll, are only halfway to possibly getting to their second BCS national title game in three years.
    “As far as our goals or things we’re trying to accomplish, that’s not even made our list,” offensive coordinator Kevin Wilson said. “We’re talking more about a young football team improving than where we’re ranked or style points, or computer rankings, or strength of schedule, or pulling for somebody to win or lose.”
    Oklahoma State came into the season returning only eight starters, with a new quarterback, a lot of youngsters on defense and expected to finish near the bottom of the South standings.
Now it’s the Cowboys, not Nebraska, who are undefeated when those two teams play Saturday in Stillwater. And Oklahoma State coach Mike Gundy refuses to say he is surprised by that.
    “I guess I was confident that those guys would be able to play better at an earlier stage in their career than the last group,” Gundy said.
    • BIG GAMES: After hosting Oklahoma to determine which team remains undefeated, Missouri goes the following weekend to Nebraska for a game that could well determine the Big 12 North winner.

    Other notable games:
— Kansas State at Missouri, Nov. 13.
— Oklahoma State at Texas, Nov. 13.
— Colorado at Nebraska, Nov. 26, farewell to the Big 12 game.
— Oklahoma at Oklahoma State, Nov. 27, South Division title and undefeated seasons on line?

    • THE NEW COACHES: New Kansas coach Turner Gill is trying to regroup his team after losing the past two games by a combined 100 points. And, remember, his debut with the Jayhawks (2-4, 0-2) was a 6-3 loss to a lower-division FCS team.
    “What has happened in the past has happened in the past and now here is a new season, per se, for us,” Gill said. “We have faith in the things we’re doing. ... A new staff, putting in a new system, particularly on offense, it kind of takes a little bit longer to get going, and a freshman quarterback.”
    Tommy Tuberville is finding out how difficult it is to have a productive running game at Texas Tech, which has long been known for its pass-happy ways.
    With an offensive line not used to running much, Tuberville knows that is “just the transition.” The Red Raiders (3-3, 1-3) are last in the Big 12 with 115 yards rushing per game, but they are still second in passing with 315 yards per game.
    “It’s like changing the language,” Tuberville said. “You’ve got to slowly learn it, got to get better at it, got to be more physical.”

    • BOWLING BAYLOR?: Baylor is 5-2 for the first time since 1995, the season after its last bowl appearance. With one more victory, Baylor will have the six wins necessary to be considered for one of the league’s eight guaranteed bowl spots.
    Yet, nothing is for certain since the Bears have the toughest portion of their schedule remaining.
    After K-State on Saturday, they still have to play Texas, Oklahoma State, Texas A&M and Oklahoma. Baylor is 5-57 combined against that quintet since the Big 12 began.
    • TEXAS BOUNCEBACK: With its 20-13 victory last weekend, Texas handed Nebraska its first loss of the season, avoided a three-game losing streak and got back into the Top 25 at No. 22 soon after ending a 10-year run in the poll.
    “The game gets our swagger back,” coach Mack Brown said. “It shows us that we can be back to where we’ve been. We just have to play well as a team together and play with confidence.”