As the Big 12 developed its reputation as a quarterbacking oasis in the past decade, an accepted truth emerged: If you don't have an experienced quarterback, you can count out a Big 12 title run.

Over the Big 12's 16-year history, only three quarterbacks have won a title as a first-year starter. Two of them played for Oklahoma, and one of them (Sam Bradford) went on to win a Heisman Trophy. The Sooners pulled off the improbable feat in 2006 after moving Paul Thompson back to starter when coach Bob Stoops kicked Rhett Bomar off the team, but the truth has been nearly ironclad: If you want to win the Big 12, you'd better have loads of experience behind center.

"This year is one of those years where there's a number of excellent quarterbacks [who] are moving on, so a new batch will be coming up," Stoops said.

For young quarterbacks, a rise to a league title or a BCS bid has never been more attainable.

Texas' David Ash, the league's sudden elder statesman, carries 18 career starts under his belt, but the next-most experienced quarterback in the league hasn't taken the field since October.

TCU's Casey Pachall hasn't officially regained his status as the Horned Frogs' starter, but he'll try to start his 18th game against LSU to open 2013 after sitting out the final nine games of 2012 to seek treatment for drug and alcohol addiction.

The rest of the league, though? Oklahoma State might be the favorite to win its second Big 12 title in three seasons, but it has no idea who its starting quarterback will be just yet after injuries led to three -- Wes Lunt, J.W. Walsh and Clint Chelf -- playing about a third of the season each and all of them topping 1,000 passing yards and winning a conference game.

Oklahoma's Blake Bell looks likely to claim Landry Jones' vacated job, but the Sooners will enter fall camp without an official announcement.

For those keeping count, that's three of the Big 12's top four teams who don't know (or at least, haven't announced) who will start their first game of 2013.

Baylor, Texas Tech and Kansas State might be in the mix for the Big 12 title, too, but only Baylor made an official announcement at quarterback, crowning Bryce Petty as the next in a long line of good quarterback play under Art Briles. Michael Brewer will continue to battle Davis Webb at Texas Tech, and Kansas State's derby between Daniel Sams and Jake Waters will leak into fall camp as well.

"There's a lot of question marks in our league, and that has not been the case the last couple of years," Texas coach Mack Brown said.

It's a whole new ballgame in the Big 12, and it's a wide-open race. The game is the same: To win in the Big 12, you have to have great quarterback play.

This season, though, the rules have changed.

"With new QBs, there are always question marks. I mean, you don't really know until you know. The only way to know is to get out on the field with them in the heat of battle and find out how they respond," Briles said. "It changes the dynamics of the league 100 percent."