Ryan Cook quickly in center for Dallas Cowboys

Ryan Cook was playing against the Dallas Cowboys in the preseason finale only a couple of weeks ago.

Now Cook is a center of attention for the Cowboys, preparing to start in the middle of a restructured offensive front in the second game of the season Sunday at Seattle. He was already snapping to Tony Romo and making line calls only two series into the season opener.

''He's really proven that he can learn things quickly,'' coach Jason Garrett said Wednesday. ''He did a really good job in the Giants game. We hope he just continues to grow in our system.''

After starting all 16 games at center for the Cowboys last season, Phil Costa dealt with back issues in training camp while two other candidates for the job, Bill Nagy and Kevin Kowalski, both sustained ankle injuries. Costa's only preseason action was 12 snaps in the preseason finale against Miami, the same game Cook was playing guard for the Dolphins two days before being traded to Dallas.

Costa, who won't play against the Seahawks, only got through the first series in the season-opening win at New York before being sidelined again by his back. In went Cook, who had previously only gotten about 10 snaps with Romo in practice before some quick warm-ups on the sideline.

''I've been around for a while. I always prepare that way because you never know. You're always one play away,'' Cook said. ''In that instance in the game against the Giants, I was three plays away.''

Despite a 24-17 victory in the opener, the Cowboys were far from perfect. Of their 13 penalties, five were false starts and two were for delay of game.

There were plenty of reasons for all the pre-snap miscues. A new center was suddenly thrown into the mix with two new guards, and it was the first game for Dallas since the starting tackles switched sides. It was also at MetLife Stadium in New Jersey against the defending Super Bowl champions and their standout defensive front.

''There are a lot of different reasons you can say this was a factor, that was a factor,'' Garrett said. ''Obviously, when guys have more experience playing next to each other or playing with each other, your chances of success are certainly greater. But we've just got to get it right.''

Their next chance comes against Seattle, 11 days after the opener.

''I was fairly comfortable. I still have a long way to go, a lot to learn. That's my sole focus here at this point, is continue to get better and improve every day,'' Cook said. ''Personally, I have to get better and improve. I have to do better at communication and getting everybody on the same page.''

Though the Cowboys like Cook's flexibility to play different positions, only one of his 40 starts his first six NFL seasons came at center. That was for Minnesota in 2010, when his other six starts were at right guard. His other 33 starts were at right tackle, including all 16 games in 2007.

Garrett said the team has long had an eye on Cook, a second-round draft pick by Minnesota in 2006 who signed with Miami last year after being released by the Vikings at the end of training camp. The Cowboys' interest became even more urgent with their line situation before this season started.

With the 6-foot-6, 325-pound Cook at center, the Cowboys are bigger in the middle. Costa is listed three inches shorter and 12 pounds lighter.

''A lot of times you target guys around the league, and you just don't have access to him,'' Garrett said. ''We've been talking about him for a couple of years, and a couple of transactions, he went somewhere else or he re-signed with his team, whatever the case has been. We saw an opportunity to get him, to add to the depth of our offensive line with a veteran player who could go in and play at a couple of different spots.''

Within 24 hours after getting back to Miami following the preseason finale, Cook was back in Dallas preparing for a season opener.

Now he's right in the middle of everything for the Cowboys offense.

NOTES: CB Mike Jenkins said he definitely will play against the Seahawks, though he didn't know how much or how he would be used. Jenkins didn't play in the opener after missing the entire offseason and all of training camp recovering from shoulder surgery. Garrett said Jenkins has ''had some good days and we feel good about it.'' The coach said playing will depend on how Jenkins responds to practice. ... CB LeQuan Lewis was signed a day after being released from the New York Jets practice squad. The Cowboys expected Lewis to be a special teams contributor.

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