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Here are 10 things to take away from the Cowboys' first preseason game.

10. That offensive line, though...

Widely regarded as the best in the NFL, the Cowboys locked in a major piece by signing center Travis Frederick to an extension worth $56.4 million ($18.2 million is fully guaranteed).

"Any chance you get be on a team, know you're going to stay here and really dig in," Frederick said in a postgame interview. "It's a good feeling to have. It takes any doubt about the future out of the way. I don't have to worry about that for a very long time."

His new deal will keep him in Dallas through 2023 (which is the same year that Tyron Smith is under contract until). Smith did not get to play in the game due to a stinger. Probably not the homecoming he was looking forward to.

Jason Garrett said Cowboys decided not to play LT Tyron Smith because he has a stinger. The former USC standout had to watch in the Coliseum — Brandon George (@DMN_George) August 14, 2016

9. Lucky solidifying his spot as kick returner?

Dallas Cowboys wide receiver Lucky Whitehead (13) races to the sideline on a first quarter carry against the Los Angeles Rams in their first preseason game at the Los Angeles Memorial Coliseum, Saturday, August 13, 2016. (Tom Fox/The Dallas Morning News) (Tom Fox / Staff Photographer)

Last season the Cowboys used six different players on kick returns and three different players on punt returns. Lucky Whitehead was one of two people to be a part of both (with the other being Lance Dunbar).

While he did dazzle at times, he went through some growing pains learning the position and had the occasional problem by fumbling. But he was still the most dynamic kick returner on the roster racking up 452 yards.

He started off the 2016 campaign with a bang returning a kick 101 yards for a touchdown (see video of the return here). The Cowboys didn't have a kick return go for a touchdown in the entire 2015 season.

Dallas needs someone to consistently fill the void Dwayne Harris left behind when he went to New York. Can Whitehead do that this year?

8. L.A. loves it some Jerry Jones

The NFL is back in Los Angeles for the first time in 22 years largely due to Jerry Jones' efforts of getting professional football back to California. He even got a "Jerry, Jerry, Jerry!" chant from the opposing fans.

In mid-January, Jones became Rams owner Stan Kroenke's biggest advocate at a meeting in Houston. He urged owners to approve the Rams' move from St. Louis. They listened, by a whopping 30-2 vote.

Jones seemed to enjoy the moment in L.A. even more than Kroenke, basking in the spotlight. Jones walked out of the main entrance nearing two hours before kickoff waving at fans. He wasn't on the field for five minutes before he posed for a selfie with former NFL receiver Randy Moss.

"You could see the buzz of activity and anticipation in and around the stadium as we came to the game in the car," Jones said. "This stadium, this city, has a football heritage that goes back several decades, and people are fired up."

Read more on Jerry's impact on Los Angeles here.

7. The good from the defense

A year ago the Baltimore Ravens were the only team to have fewer interceptions than the Cowboys (Dallas had eight a year ago to Baltimore's six). They got two interceptions against the Rams Saturday courtesy Mark Nzeocha and Deji Olatoye.

Nzeocha, who intercepted Jared Goff, didn't play last season because of a surgically-repaired knee. He's been showing a lot of upside the last couple of weeks at middle and weakside, according to SportsDay's Jon Machota. Olatoye has been working at multiple defensive back spots. He's one of only four defensive backs to record an interception last season for the Cowboys.

6. Improvements needed on defense

The defensive line is going to be one of the biggest question marks for Dallas given the suspensions to ends Randy Gregory and DeMarcus Lawrence. The Cowboys rolled with David Irving, Ryan Russell, Shaneil Jenkins and Mike McAdoo at end in Saturday's game.

Irving started at left end and Russell started on the right. Neither recorded a sack. Jenkins, who signed with the team last week, was the only Cowboys defender to sack a quarterback Saturday.

The versatile tackle/end brought down this year's first overall draft pick, Goff, late in the second half for a nine-yard loss.

"He's definitely a hard-working guy," Russell said of Jenkins. "He knows the plays, he knows all the positions. Very strong guy."

Irving did't view his performance in as positive a light. Click/tap here to read more.

5. Dez is back

Dallas Cowboys wide receiver Dez Bryant (88) and Los Angeles Rams running back Todd Gurley (30) hug one another following their first preseason game at the Los Angeles Memorial Coliseum, Saturday, August 13, 2016. The Cowboys lost 28-24. The two traded jerseys. (Tom Fox/The Dallas Morning News) (Tom Fox / Staff Photographer)

The wideout has been chomping at the bit to get back onto the football field. He did so in a big way with two catches and a touchdown. Did Bryant have to talk the coaches into letting him play?

"I was going out there regardless," he said. "There was no way I was going to sit. I needed to be on the field. I wanted to see something different. I wanted to test myself."

Head coach Jason Garrett elaborated a bit more:

"He played about the amount of snaps we wanted him to play," Garrett said. "He's been away from it and he needed to be out there. He needed to run routes against an NFL corner in a game setting. He'll continue to do that over the course of the preseason. He was ready for it. Mentally and emotionally he was ready to play and I thought he did a really nice job taking advantage of his opportunities."

4. His sidekick Terrance Williams had a good day

When Bryant went down a year ago, Williams was poised to take over the No. 1 receiver spot. It didn't go so well. He did have Brandon Weeden and Matt Cassel throwing to him, but he wasn't able to fulfill that No. 1 role.

Now that Dez is back, Williams is looking like his old self, which included a 32-yard touchdown reception against L.A.

Terrance Williams has looked good throughout camp. He's in for a big payday if he keeps this up — Jon Machota (@jonmachota) August 14, 2016

3. Dak Prescott had himself a day

He went 10-12 passing (with two drops from tight end Geoff Swaim) for 139 yards and two touchdowns. Not bad for a rookie, right? See his highlights here.

Offensive coordinator Scott Linehan had this to say of his QB:

"I thought Dak was really sharp for a first start. He didn't act like it was too big of a thing. It was good to see," Linehan said. "He shows a lot of maturity for this point in his career.

"He gets himself really well-prepared for each day, not just this game. He's really a mature kid. He's ahead of his years. There's never a day that we don't feel real good about his development and where he's coming. We're real excited about where he's headed and he's shown us a lot of good things and I'd be surprised if he doesn't continue."

2. He put QBs drafted ahead of him to shame

Dallas Cowboys quarterback Dak Prescott (4) keeps the ball and rushes past Los Angeles Rams defensive back Coty Sensabaugh (21) in the second quarter of their first preseason game at the Los Angeles Memorial Coliseum, Saturday, August 13, 2016. (Tom Fox/The Dallas Morning News) (Tom Fox / Staff Photographer)

From columnist Tim Cowlishaw:

On the one hand, it's an exhibition game, a football friendly, with relatively little at stake. On the other hand, nearly perfect is still nearly perfect. And Prescott looked far more prepared than anyone could have anticipated after two weeks of practice up the road in Oxnard.

Let's put it this way. No position in sports gets the pre-draft scrutiny of an NFL-bound quarterback. It involves years of tape and then months of workouts, interviews and inspection from head to toe. And, still, scouts never really know.

The quarterback picked at the top of the draft, Goff, made his debut for the Rams and completed four of nine passes for 38 yards. He also threw an interception to Cowboys linebacker Mark Nzeocha.

The quarterback picked No. 2 by Philadelphia, Carson Wentz, went 12 of 24 for just 89 yards with an interception Thursday night. He also suffered a hairline fracture in his ribs that could set him back for a few weeks.

Continue reading here.

1. How Prescott impressed Jason Garrett

From SportsDay's Kate Hairopoulos:

But where Prescott may have stood out the most in head coach Jason Garrett's eyes, came when the former Mississippi State Bulldog was playing behind the chains.

Garrett talks about evaluating quarterbacks on myriad elements, including how they handle trouble.

In the second quarter, Prescott faced it for certain: second and 34 from the Los Angeles 48 after penalties had backed up Dallas.

Prescott found receiver Devin Street for an 8-yard gain.

Third and 26 from the Los Angeles 40: The Rams blitzed and Prescott scrambled for a 14-yard gain. The Cowboys were back in field goal range. Kicker Dan Bailey converted the 44-yard attempt.

"Thought he handled that situation very well," Garrett said. "That's something you can try to emphasize to the quarterback between plays, managing the situation, know where you are on the field. But you certainly got the sense that he knew that already.

"Really big play making the play with his feet to get us back into field goal range to give us a scoring opportunity right there."

Continue reading here.

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