As they prepare for their Week 2 match-up with the Seattle Seahawks, the Dallas Cowboys held practice Thursday and several stories came to light.

While they played better than expected in their Week 1 victory over the New York Giants, the Cowboys' offensive line continues to struggle with injuries.

Center Phil Costa sat out of practice Thursday and is expected to miss Sunday's game versus the Seattle Seahawks. Guard Ryan Cook will replace him in the starting lineup. Costa left after the Cowboys' first offensive series against New York as his back started to act up again, and Cook stepped up.

Dallas traded for Cook on Aug. 31 from the Miami Dolphins just after training camp broke and the Cowboys made their final roster cuts.

Costa, along with nose tackle Jay Ratliff and safety Matt Johnson, did not practice Thursday. Ratliff could be doubtful against Seattle, as he recovers from a high ankle sprain suffered during the preseason.

Replacing Ratliff against New York fell to defensive tackle Josh Brent and defensive end Sean Lissemore, and both could fill his role again Sunday.

The Cowboys' biggest injury concern has been star tight end Jason Witten, who is still recovering after a lacerated spleen kept him out for most of the preseason. Witten played against the Giants, but had only two catches for 10 yards. Still, his performance was seen as an inspiration by many players and head coach Jason Garrett.

On Wednesday, Witten participated in a full practice and said he is feeling much better since he sustained the injury Aug. 13 against the Oakland Raiders. He also revealed he is wearing some extra padding to protect the injury.

"I've got padding there and I'm going to do those things," Witten told "The good news is unlike an ankle or hamstring, something that can be lingering there for weeks, this is something that I feel good when I'm out there practicing, running doing all that stuff. I don't see any setbacks that will get in the way here."

On a lighter note, Dallas has a new product for fans. The Internet and Twitter exploded when team owner Jerry Jones was spotted handing off his glasses for a cleaning in his suite during the New York game.

Later, the cleaner was identified as Jones's son-in-law Shy Anderson. Anderson told the Dallas Morning News that he ordered wipes special for his father-in-law. Now they are available to the public.

On Thursday the Cowboys put new micro fiber wipes, called Jerry Wipes, on sale for $2.99. Anderson told the Morning News the proceeds will go to a Salvation Army program that provides glasses to children in need.