These are days of change in the Big 12 Conference.

Kansas State is a defending champion for the first time in 70 years. New Nebraska coach Bill Callahan has run the option right out of Lincoln. The Big Red Machine is now a passing offense.

Missouri believes it may have a Heisman Trophy winner at quarterback.

But not everything about this conference is in flux.

Oklahoma still strikes fear in most opponents, and Texas once again may have a quarterback combination, uh, rotation, er, collaboration. Whatever.

Kansas State won the league title in 2003, but second-ranked Oklahoma won’t let the Wildcats keep it without a fight.

Not with nine starters returning from an offense that averaged 42.9 points per game, including Heisman Trophy-winning quarterback Jason White.

Not with a defense that returns seven starters and replaces Butkus Award winner Teddy Lehman at linebacker with Lance Mitchell. Mitchell was supposed to be a standout last year before a knee injury forced him to miss the season.

And not as long as Bob Stoops, the coach who routinely calls the biggest plays in the biggest games, still is the head coach.

“We accomplished more than most teams last season,” said defensive end Dan Cody. “Granted, we didn’t finish the way we wanted to, but it gives us something to build on for this year.”

White returns with a sixth year of eligibility eager to restore a reputation that took a beating with sub-par performances in the two losses. He’s the first returning Heisman winner since BYU quarterback Ty Detmer in 1991.

Detmer didn’t win a second trophy, and White knows it won’t just be handed to him this year either. He’s not even the league’s preseason offensive player of the year. That honor went to Kansas State running back Darren Sproles.

White and Missouri’s multitalented Brad Smith shared preseason honors for all-Big 12 quarterback.

“I’m sure I’m not the only player left off an All-American list that’s going to be on an All-American list,” White said. “It’s motivation to work hard throughout two-a-days and throughout the season.”

White will have plenty of help.

His entire offensive line returns, as does the Big 12’s top receiver, Mark Clayton. And if freshman Adrian Peterson lives up to his billing as the nation’s top recruit at running back, the rushing attack will be improved as well.

So dominant through most of last season, the Sooners must plug holes on defense. New co-coordinator Bo Pelini — from Nebraska, no less — must account for the loss of All-Americans Derrick Strait at cornerback and tackle Tommie Harris.

Despite losing the Big 12 title game to Kansas State and the Sugar Bowl to LSU, the Sooners — and their fans — expect to chase titles again this year.

Stoops won the national title in 2000. The Sooners wouldn’t think of accepting anything less.

“We’re about winning championships,” Stoops told OU fans at a summer meet-and-greet session. “I understand that, I love it, and that’s what we’re after every single year.”

A capsule look at the teams in predicted order of finish:

North

Kansas State: Mighty-mite Sproles is coming off superb ’03 when he set the school single-season rushing mark with 1,986 yards. …. One of the losingest programs of all time, the Wildcats have won at least 11 games in six of the past seven seasons.

Missouri: The Tigers were the only North team to go undefeated at home last season. They weren’t nearly as good on the road (2-5). …. Smith was 23 yards short of becoming the first player in NCAA history to pass for 2,000 yards and rush for 1,000 in a season.

Nebraska: In the new West Coast offense, QB Joe Dailey had 16 pass attempts in the first quarter of the Huskers’ Red-White intrasquad game in the spring. That’s more than the 15 attempts Nebraska averaged per game last season. …. Expect these numbers to change: The Huskers last season ranked 12th in the Big 12, and 114th nationally, in passing.

Colorado: Scandal loomed over the Buffaloes during the offseason. But coach Gary Bennett is back on the sideline after a spring suspension for insensitive remarks he made about a former player who claimed she was sexually assaulted. …. Six players transferred, including last year’s starting tailback, Brian Calhoun.

Kansas: The Jayhawks return eight starters on both offense and defense. …. Defense was one of the worst in the country, giving up more than 30 points and almost 200 yards rushing per game …. DE John McCoy was called up with his Army Reserve unit and may be headed for Iraq.

Iowa State: Cyclones lost their final 10 games last season. … DE Jason Berryman, the Big 12’s defensive newcomer of the year in 2003 and the Cyclones’ MVP, has been suspended indefinitely after being charged with second-degree robbery, his second offense in three months.

South

Oklahoma: White’s health will be a key concern again this season. The 24-year-old had two seasons cut short by knee injuries and was banged up in the two losses last year. When he was healthy, he was near perfect with 3,846 yards passing and 40 touchdowns. …. Pelini’s on board because Bob Stoops’ brother, Mike, now is the head coach at Arizona.

Texas: The Longhorns got a huge break when running back Cedric Benson and linebacker Derrick Johnson, two of the best players in the nation at their positions, chose to stay for their senior seasons. …. Texas has lost four in a row to the Sooners. …. Vince Young or Chance Mock at QB? Coach Mack Brown says Young is the starter — but for how long?

Texas Tech: Coach Mike Leach must replace departed QB B.J. Symons, who threw for an NCAA record 5,833 yards. Fifth-year senior QB Sonny Cumbie, who never has started a game, won the job in preseason. …. With its wide-open offense, Tech always is a threat, but the Red Raiders have yet to make a run at division title under Leach.

Oklahoma State: Josh Fields set an Oklahoma State career record with 55 touchdown passes but left the Cowboys after the Chicago White Sox selected him in the first round of the MLB draft. …. Les Miles is the only coach with a winning record (2-1) over OU’s Stoops. …. For the second straight year, the Cowboys play Oklahoma and Texas in consecutive weeks.

Texas A&M: Coach Dennis Franchione promises it will get better in year two. It can’t be much worse than last year’s 4-8 record, the first losing season at A&M in 21 years. …. Only eight starters return from a squad that lost its final three games by a combined score of 168-37, including a 77-0 rout at Oklahoma.

Baylor: Bears must replace 1,000-yard rusher Rashad Armstrong and leading receiver Robert Quiroga. … Coach Guy Morriss has big concerns about the offensive line, where three starters had surgery. … The Bears haven’t won more than three games in a season since 1996.