SANTA CLARA, Calif. -- With starting left tackle Tyron Smith out as the Cowboys take on the 49ers in Levi's Stadium, fourth-year backup Darrion Weems will get the start. Weems' first duty is protect quarterback Tony Romo's blindside, who has declared he will play against San Francisco.

Cowboys Executive Vice President Stephen Jones told CBS 11 [KTVT] that he has full confidence in the 26-year-old.

"First of all, I think he can do it," said Jones. "I think he's shown, flashed the skills that he needs to to really play that position the way we need it played. I think he can swing. I think he can go left or right. I think it's just a matter of getting in there and getting the reps."

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Weems had a pedestrian outing last week in San Diego despite having all four quarters to have a good outing against the Chargers. Nonetheless, Jones recognizes the tough task that was placed on Weems during pregame warm-ups.

"He played right tackle all of camp, got told right before he walked on the field he was going to play the whole game at left tackle," Jones said. "So, we really feel like he can do it."

If Weems ultimately cannot be the team's swing tackle, the Cowboys won't be able to rely on third-round pick Chaz Green as a contingency plan. Green is expected to start the season on the PUP list with a hip injury, meaning he would have to sit the first six games of the season. Dallas would have to go to a "Plan C" if Weems can't handle the swing job, but Jones would still feel fortunate.

"We're lucky to have an offensive line there where some guys can swing around, starting with a guy like Zack Martin. Then we also have a guy who played tackle in college in La'el Collins. As I've said all along: player acquisition is 365 days a year. And Jason [Garrett] does a great job of telling our players that. You're not just competing against the guys on the field at the time, but you're also competing other guys in the NFL.

"So, we'll take a long, hard look at this, but I'm a big believer that Weems can get this done."

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