Smith and Costa were full participants in practice but Nagy's injury is new and it's possible his health forced the Cowboys to give Derrick Dockery some first-team reps. The Cowboys have been positive when talking about Nagy's efforts in the Week 1 loss to the New York Jets, but Dockery has started 111 games at guard in his career and having an experienced player at that spot could help the offensive line.
"It’s an excellent opportunity for me. I want to take full advantage of it," Dockery said. "We’re playing a talented tough team in San Francisco, so it’s going to be a very tough matchup first game. I’m looking forward to the opportunity."
Dockery was signed Sept. 5 and he's still learning the Cowboys' offensive scheme. The last two seasons in Washington, Dockery played in Denver's one-cut zone blocking scheme whereas in Dallas he plays in a traditional zone scheme.
"It’s coming along," Dockery said of learning the scheme. "I’m in my playbook every day, every night. It’s coming to me pretty easily. I’ve been in a similar offense before, so the terminology is the same. Little wrinkles here and there. I’m just right now talking to Tony [Romo], [Doug] Free, [Kyle Kosier] and seeing as far as the snap count some of the little details that might help me while I’m out there playing."
Offensive line coach Hudson Houck said he's not sure if Dockery will start on Sunday.
It doesn't appear the Cowboys want a rotation with their linemen because communication is important and they don't want to mix and match players during a game.
"You want to have guys who can communicate together," Houck said. "Communication sometimes on the right side is different than communication on the left side. You need guys in there who can work together in any environment, whether in an office environment, whether in a family environment, communication is pretty important."