FRISCO, Texas -- Since he became the Dallas Cowboys' starting quarterback in 2006, Tony Romo has never had any competition.

Every backup has been a former starter no longer quite good enough to start such as Jon Kitna, Kyle Orton or Brad Johnson -- or clear subordinates the team never really wanted to see in a game.

The Cowboys have been Romo's team for a decade no matter the circumstance or the coach.

Those days have ended.

Dak Prescott, a rookie taken in the fourth round with the 135th pick, has played so well that no one knows for sure whether Romo will ever start another game.

If Romo, who suffered a compression fracture in his back during the preseason, gets the job back, he'll compete with Prescott to keep it. If Prescott is named the starter -- the most difficult professional conversation coach Jason Garrett will ever have -- then Romo will compete in practice to get his job back.

"There's ebbs and flows to everything in life and different seasons to it all. We all go through different adversities at different times," Romo recently told ESPN.com in a conversation about his journey from undrafted free agent to 10-year starter with the Cowboys.

"It's the same thing about playing quarterback. It seems so normal -- the ups and downs -- and everything that goes along with playing quarterback. When you first start playing, you think everything is going to be great and you're never going to lose.

"The game is a great game, but you have to keep getting better. The game will humble you if you don't continue to be at your best week in and week out."

This situation is new to Romo, but it's not new to professional football. Aging stars always seemingly spend their last few years trying to hold off some talented newcomer.

The only reason Tom Brady took Drew Bledsoe's job is because coach Bill Belichick viewed Brady as a guy who could be a long-time starter once he had an opportunity to play.

The only reason Parcells benched Bledsoe for Romo is because he viewed Romo as player who could start for decade. All he needed was a chance.

Now, Prescott is trying to take Romo's job with a series of stellar performances no matter how many times Prescott tells us this is Tony's team. If the Cowboys ultimately choose Prescott over Romo, it's because Garrett, Jerry Jones and Stephen Jones view Prescott as a player capable of starting for a decade.

How ironic.

If Prescott claims the job, Romo won't back down. It's not in his personality. Anyone in that locker room who's played with Romo will tell you his competitive spirit has no bounds.

"He's a great competitor," Garrett said. "He loves to play. He loves to be in competitive situations. He loves to be part of a team. That's what he's all about."

Romo missed parts or all of 14 games last season. He's missed all six games this year, and Prescott is expected to start against Philadelphia on Oct. 30, which would make it 21 of the past 23 games Romo has missed.

Prescott has passed for 1,486 yards with seven touchdowns, one interception and has a 103.9 passer rating to help the Cowboys start 5-1.

Every time Prescott meets with the media he gets questions about Romo and how long he'll be starting. Garrett and Jones receive the same type of questions.

Since his injury, Romo has yet to discuss whether he expects to keep his starting job, what he thinks about Prescott's performance, or his future.

Romo's been on the sideline during games, helping Prescott when he can. And Prescott has been nothing but complimentary toward Romo.

But there's only one starting quarterback, and each man covets the position.

"If you have a really good team around you, it will make you look better," Romo said as he talked about his ascent from backup to starter.

"The hard part for quarterbacks is carrying bad teams. If you're able to do that -- if you're able to carry an average team, you’re going to play quarterback for a decade or longer because, ultimately, your team is not going to have a 10-12 year run of great teammates and great players.

"It just isn't possible with free agency, age, injury and the salary cap. If you're able to survive those years when your team isn't that good ,and you're carrying them and giving them an opportunity to compete game in and game out, then organization is always going to have you there."

Unless Prescott is playing so well that Garrett can’t justify taking him out of the lineup.