Arkin is getting the bulk of the snaps with the first team in practice while Costa remains Andre Gurode's backup at center. Costa gets snaps with the second and third teams from time to time at guard.
Holland was the projected starter at right guard, but his injury forced the Cowboys to make all sorts of switches along the line until he returns.
"I think we obviously needed a few young guys to step up to really help this football team this year," quarterback Tony Romo said. "Without the offseason, it’s been kind of a crash course. Mistakes are going to happen. That’s part of the growing curve. We obviously need them to step up quickly, and they’re doing a good job battling every day. We just need to keep grinding and I think a feeling we’ll continue to grow as a football team each week because of that."
You might want to lean on giving the job to Holland, who despite his weight issues (340 pounds) is still a solid player in the organization's eyes.
But to have two younger players with left tackle Doug Free, who started 16 games at the position in 2010, should be helpful. Line coach Hudson Houck has praised Arkin and Costa for their work this summer.
"You see them just when you’re in the huddle and things of that nature," Romo said. "It’s a battle. It’s going to be a good battle. I don’t know what the coaches are thinking in that whole process, but it’s an important position and we need to have someone play good football. I know that."