According to Dallas Cowboys.com, the Cowboys scheduled a workout for three veteran guards on Thursday afternoon: Montrae Holland, Derrick Dockery and Daniel Loper.

This is a clear indication that things are not going as planned for the interior of the Dallas line. Injuries have played a significant role, but it may also be a sign that Callahan isn't sold on what they have in camp.

Although it would be best for Dallas if their younger players were healthy and up for the task, making an early move to bring in reinforcements is a sound decision.

Montrae Holland, provided he is in decent shape, would seem like a no-brainer. If you will recall, Dallas' running game was abysmal to start the season in 2011. It was only after they inserted Holland into the lineup that they began to open up holes.

Much of the credit was given to the fullback Tony Fiametta, and indeed, he was a big part of DeMarco Murray's success. Still, Holland was at least as important to the sudden emergence of the Cowboys' running attack.

According to Pro Football Focus, Holland was the league's 16th rated guard last year. That isn't bad when you consider that the list included 78 guards. Holland ranked ninth in run blocking and 21st in pass blocking.

Dockery only received 133 snaps last year and didn't grade out terribly well. He was ranked 84th out of 136 guards who saw the field at all in 2011. Not terribly inspiring. Loper didn't play at all last year.

So, out of this group, it's Holland that Cowboys fans should be excited about. He was clearly one of the top guards in the NFL last year, and he was the second best offensive lineman on the Cowboys—the first place obviously going to Tyron Smith.

Montrae Holland
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Having Holland starting at one of the guard spots would give Dallas some much-needed talent and experience in the middle of the line, an area of great concern. His presence will not only help with the position he takes but will also help the center and the tackle.

If Holland starts at right guard, Doug Free will be saying prayers of gratitude. Especially during the Eagles games, when Free has to contend with Jason Babin coming at him.

If Holland starts at left guard, look for the Cowboys to run directly at some of the most fearsome pass-rushers, giving Holland and Smith the opportunity to pound on them as often as possible. Running directly at guys like Jason Pierre Paul and Trent Cole makes sense, given their athleticism and ability to pursue plays. It would also give Holland and Smith an edge in pass-blocking on play-action.

Make no mistake about it: Even with all of the subplots and questions swirling around Cowboys camp, the Holland workout and possible signing is the most significant news to emerge from camp thus far.