NORMAN, Okla. -- Those hoping for some grand revelation to come out of the quarterback competition this spring -- or for that matter, Saturday’s Red-White spring game -- might want to sit back.

This could take a while.

Blake Bell, Kendal Thompson and Trevor Knight all entered the spring vying to be Oklahoma’s next starting quarterback. Barring something unforeseen in the next week, they’ll all exit the spring doing the same.

“None of those guys have earned it yet,” said offensive coordinator and quarterbacks coach Josh Heupel. “It doesn't mean they're not playing well. It's just nobody has earned that spot.”

While evenly splitting up time with the first-team offense, all three quarterbacks have had their moments. Had their mistakes, too.

During Sunday’s two-hour scrimmage, Bell, Thompson and Knight all engineered touchdown drives. All three had nifty dashes out of Heupel’s new-look offense that relies on the legs of the quarterback.

But Knight threw a pick-six to freshman safety Ahmad Thomas. Thompson was also intercepted while trying to make something happen downfield. And Bell took two sacks on his first series, which ended with a three-and-out.

“They’ve all made their fair share of mistakes,” Heupel said last week. “But they’ve learned from them, not repeated the same mistake, and gotten better. I’m not excited or pleased where they’re at, but I think they’re going in the right direction.”

Which is why this quarterback battle, like that of Sam Bradford, Joey Halzle and Keith Nichol in 2007, figures to run deep into August.

By all accounts, Bell, Thompson and Knight have all played well. But none well enough to put distance between himself and the others. That’s not likely to happen with one spring game, either.

“You hope somebody separates themselves,” Heupel said. “But if they don't, you go into training camp. You can only name a starter once somebody has earned that position.”

Good luck handicapping who that will be.

Thompson, the so-called dark horse of three, has exceeded outsiders’ expectations to ensure the competition will be a three-way race. Thompson also had a strong weekend, capped with perhaps the most impressive scrimmage Sunday of the quarterbacks.

“He’s extremely competitive, had a great offseason physically, grown a lot mentally from where he was a year ago,” Heupel said of Thompson, who last fall more times than not was the last guy to leave the practice field.

“He’s given himself a chance to be the guy."

Knight will have his chance, too. An exceptional athlete in the mold of Texas A&M’s Johnny Manziel, Knight has flashed plenty of his big-play potential this spring.

So has Bell, who, despite some inconsistencies throwing the ball, remains the favorite because of his game-time experience.

“All of them have handled what we’re doing offensively, command, communication in a really good way,” Heupel said. “All three of those guys have continued to get better day by day, week by week.

“They continue to play that way and improve upon that, they’re giving themselves the chance -- whoever the guy is -- to play at a high level.”

Whoever the guy is, don't expect him to be revealed in the spring game. This derby figures to continue on well past Saturday.