SAN ANTONIO -- The yin and yang of training camp is usually that a surprise player's emergence means the end of a dream for someone else.
That scenario appears to be playing out at the Dallas Cowboys tailback position, where former practice squad player and undrafted free agent Lonyae Miller has become a strong candidate to make the team's roster.
With the Cowboys likely keeping only three tailbacks -- starter Felix Jones and third-round pick DeMarco Murray are locks -- that could make Tashard Choice the odd man out.
Choice has been sidelined since the opening day with a strained calf, giving Miller the opportunity to get more reps.
So far he has made the most of it, drawing raves from the coaches since Day One of camp. Miller scored a couple of touchdowns in the team's Blue-White scrimmage Sunday.
He could really take a huge step forward with another strong showing in Thursday's preseason opener against Denver.
"If someone goes down, you've got to step up and fill their shoes," Miller said.
"I feel like I've done that. But I've got to put this one behind me and continue to get better. ... I've got to continue to grind and come out Thursday against Denver and have a great game."
Choice has heard the talk and is not planning to go down without a fight. After getting morsels of work playing behind Jones and Marion Barber the past three years, he has looked at the 2011 season as an opportunity for a bigger role. Barber was cut, opening up at least a spot for a short-yardage role, if not more, for Choice.
The passionate former Georgia Tech star initially took to Twitter to confront the speculation of him possibly being on his way out in Dallas.
"Well, since the experts say I'm getting traded or cut cause I can't practice and my boys are practicing well then where I'm goin? My haters," Choice tweeted Monday morning.
Later in the day, Choice added that "People don't know what they are talking about. I'm going to roll this year."
Choice said he is expected to return to practice next week, but he indicated it could be sooner.
"Today is a big day for me," Choice said of his rehab.
He said when he does return to the field he will be ready to compete.
That would be wise because even coach Jason Garrett acknowledges that Choice's injury has not helped his situation.
"It's for worse because you want to practice," Garrett said. "It's an important time of year for everybody to practice."
Garrett has been extremely impressed by Miller's development. He came to the Cowboys' camp last season as an undrafted free agent out of Fresno State. He spent much of the year on the practice squad before joining the active roster late in the season.
"When we first got Lonyae, it was hard not to like his physical ability," Garrett said. "He's a big kid, and can run. As he's progressed in our system, he's really grown a lot. He's come back this year a much more mature player. He's very comfortable with his run-course as a runner and a blocker in the run game. I think he's impressive running routes as well."
Miller was the lone back at the player-run practices during the lockout.
"I feel like I have improved from last year," Miller said. "It's just been about putting in extra time. I was able to get into my playbook and get some reps with the older guys and I feel like it's carrying over to here. I'm able to play faster, play smarter and limit my mistakes and really be alert in certain situations."
The 6-foot, 232-pounder is the biggest back on the roster, making him also a possible short-yardage option with Barber gone.
That he also plays special teams gives him another edge on Choice, who has been openly criticized by owner Jerry Jones for being a less-than-stellar special teams performer.
"He has done a very good job on special teams, on coverage and return teams," running backs coach Skip Peete said. "That is what you like from your non-starter, for them to help on all special teams. That is not always the case."
Clarence E. Hill Jr., 17-390-7760