The seventh-round pick from Wisconsin is back at left guard, working with the first-team offense.
For now, Nagy seems to be leading the pack that also includes the injured Montrae Holland, rookie fourth-round pick David Arkin, and possibly Phil Costa, the backup center whom owner Jerry Jones said caught his eye the most during training camp.
But coach Jason Garrett said Nagy held his own with his starting role.
"Nagy did a nice job. I think our offensive line played fairly well against (San Diego's) first unit," Garrett said. "I think it's still a work in progress for each of them individually and then working collectively. I did think we ran the ball well, I thought we protected Tony (Romo) well and Nagy was a part of that."
For Nagy, his thought process hasn't changed.
"It's about a chance to compete," he said. "That's why we play this game. You get to compete against great athletes every play. So for me to start, I treat it like another opportunity to prove myself and get better. Whether you're starting or not, it's just football. As long as I stay prepared, I have confidence in my abilities."
Nagy is the third different player to work with the first-team at left guard and if Holland comes back soon, he might be the fourth. Holland has been rehabbing from a sore back and knee injuries.
Arkin began camp at left guard while Kosier sat out because of the free agency rules. After Kosier returned, he was later moved to right guard, putting Arkin back on the left side, where he started against Denver.
But that's when Nagy took over and for now, it appears it will remain his job to lose.