Dallas Cowboys rookie guard David Arkin has made his share of mistakes at training camp, but most of his miscues elicit only a shrug from coach Jason Garrett.

That's typical of Garrett, who doesn't mind when youngsters screw up if it's clear they're trying to do the right thing.

And nearly all of Arkin's errors fit that description.

“We like his aggressiveness,” Garrett said of the fourth-round pick from Missouri State. “He plays with great intensity. He's physical. That's what we saw on tape, and he's shown that in training camp.

“What we really like about him is he makes aggressive mistakes. Often times, he's not blocking the right guy, but he's getting after him, not hesitating.”

Carrying 307 pounds on a 6-foot-5 frame, Arkin is a tad undersized for an NFL interior lineman. He said that fact has a lot to do with his tenacity.

“That's just the way I have to play to be successful,” said Arkin, 23. “If I'm not being aggressive, I'm not going to be successful. That's the way I was taught to play. I'm not the biggest, strongest, fastest guy, but I've got some good athleticism.

“If I just play hard, that's one thing I've got in my pocket.”

With veteran Montrae Holland day to day with a back injury, Arkin has been logging reps with the first team at both right and left guard. He started at right guard in the Blue-White scrimmage Sunday, but the Cowboys have since moved him to left guard so he could be paired with veteran tackle Doug Free.

The move also allowed veteran left guard Kyle Kozier to slide to the right side and help first-round tackle Tyron Smith with protection calls. With Holland expected to miss the preseason opener against Denver on Thursday, Arkin is expected to start at left guard.

No matter where Arkin lines up, the Cowboys know he's going to hustle.

“What happens a lot with the younger guys is they're not sure, so they come off the ball slowly,” Garrett said. “They're hesitant. They're indecisive. And you really don't get a chance to see them as players.

“(Arkin) has done a really nice job of firing off of the ball and blocking the guy (while thinking), ‘Oh, it's the wrong guy, but they've got 11, we've got 11, I'm getting after this guy.' We like that about him.”

The Cowboys have seen the same aggressiveness from Smith. During the scrimmage, both rookies held their own against the first-team defense.

“Both of those guys have a long way to go,” Garrett said. “It's still early for them, but it was nice to see them in that situation. Neither of them has backed down, and they're blocking some very good, veteran players. You just want to see them keep coming, because if they keep going about it that way — and obviously (offensive line coach) Hudson (Houck) does a great job coaching them — they'll continue to grow.

“They might be striking out every so often, but they're stepping back in there and taking a swing the next time up.”

One big difference between the two: Smith is from Southern Cal, while Arkin hails from a Football Championship Subdivision (formerly Division-I AA) school.

“(Arkin) is a smaller school guy, so the hump for him is big, but it's big for anybody,” Garrett said. “He still has a lot to learn. He doesn't know what he's doing yet, both from a scheme and technical standpoint. But he's going about it the right way, and he's grown a lot just in the (12) practices we've had here.

“There is a lot we are throwing at him. From an offensive standpoint, the looks on defense are difficult. Then blocking the guys is difficult. But he's hanging in there and fighting.”