AP Sports Writer
IRVING, Texas (AP) -- Jerry Jones opened training camp with stories about how young his Dallas Cowboys were. He told a few thousand fans at the kickoff luncheon that many of those players faced an "uphill battle."
Not exactly Super Bowl talk from an eternally optimistic owner who has made such preseason predictions a few times.
The Cowboys have 34-year-old quarterback Tony Romo coming off back surgery, and Rolando McClain possibly starting at middle linebacker just a few months after deciding to retire. Not to mention a defensive line lacking star -- and possibly pass-rushing -- power heading into Sunday's opener against San Francisco.
"I think there is a difference being optimistic and assessing the odds," Jones said after the Cowboys finished a winless preseason with a 27-3 loss to last week. "You've got guys out there, no-name guys. You've got guys out there who retired. You've got guys who are coming back from injury. Man, this is a 'to prove' group."
Jones still includes coach Jason Garrett in that group. Even though a youthful roster is loaded with questions about a defense that gave up the most yards in the league last year, Jones isn't ready to commit to Garrett beyond this season.
"If I said that, I'd be giving him a contract and that's not how we're operating here," Jones said. "I in no way have shut that door. But I have already decided that we were going to operate this year with his contract status the way it is."
Garrett was at the center of reshaping a roster that has gone from one of the oldest in the league to one of the youngest in just a few seasons. Meanwhile, the Cowboys have finished 8-8 and missed the playoffs in all three of Garrett's full seasons.
Those three years ended with losses to NFC East rivals with playoff berths on the line. If Dallas misses the playoffs again this season, it will match the franchise record of five straight years without a postseason trip.
"We started with a plan to make the team younger, to build the team the right way, to bring the cornerstone pieces in, and we feel like we've done that," Garrett said. "Now is that job complete? It's not even close to complete. We understand that."
The Cowboys have avoided flashy first-round draft picks that Jones likes -- he can't stop talking about how tempted he was to take Johnny Manziel this year. Instead, they've picked an offensive lineman first in three of the past four years.
But Garrett might not be around to finish the rebuilding of a defensive line trying to replace DeMarcus Ware after the franchise's career sacks leader was released this offseason in a salary cap move.
"The guys that are available to us, we're going to give them a chance to show what they can do," Garrett said. "Hopefully they've grown with that experience, and we'll get some of the veteran players back who haven't been with us, practicing and playing as much as we would have liked. But that's just the reality of it."
And those defenders are aware of the reality.
"There's very low expectations for this defense," said defensive tackle Henry Melton, the team's biggest free agent signing getting ready for his first game since tearing a knee ligament in Week 3 last year with Chicago. "They're going to see Sunday that it's going to be a different squad."
Jones is counting on that "to prove" mentality.
NOTES: The Cowboys signed S C.J. Spillman, a special teams ace who will face his old club Sunday. He spent three-plus seasons with the 49ers, who cut him last week. ... Dallas also added LB Korey Toomer and FB Nikita Whitlock, who is on the practice squad. ... S Ahmad Dixon and DB Jemea Thomas were waived. Dixon was a seventh-round pick, and Thomas was claimed on waivers from New England last week.
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