Cowboys making changes to offensive line

IRVING, Texas -- The Cowboys will have some noticeable changes on the offensive line when the season opens against the New York Giants on September 5.
Last year's top pick, Tyron Smith, is moving to left tackle after starting all 16 games at right tackle in 2011. Doug Free, last year's left tackle, is moving back to the right side, a position he played in 2009.
But the transformation also includes new offensive line coach, Bill Callahan, and two new free agent guards, Mackenzy Bernadeau and Nate Livings.
The two newcomers are projected to be starters. Callahan said Saturday that Livings will begin camp at left guard and Bernadeau at right guard.
"That's where we're going to start it, and we'll go from there," Callahan said. "As I told them, we're going to be flexible, we'll be fluid with both of them, so when we're in camp, there's a possibility of Mack going to left and Nate to the right. We'll see how it plays out, but that is the starting point."
Callahan said there were two reasons the Cowboys liked Bernadeau and Livings in free agency: 1. They Cowboys were looking for the best available players at those positions, 2. The Cowboys were looking for experienced players that were strong in the pocket.
The only position along the offensive line left to figure out is center. Phil Costa started every game at that spot last year and is projected to line up there again in 2012. But Bill Nagy, a seventh-round pick in 2011, will also get a look at that position.
"The good thing about Bill is that he's very versatile, having played both guard spots a year ago," Callahan said. "He's trying to improve his craft this season at that position as well as learning all the new center calls and techniques, so what we're doing is basically cross-training all those players."
For the unit to reach its potential, Smith's transition will likely be the key. Can the 21-year-old effectively protect Tony Romo's blind side? Callahan said Smith learned a lot from lining up next to Kyle Kosier last season. Building similar communication with Livings could help make for a smooth conversion.
"Just having three weeks into this, it's been real positive from that aspect," Callahan said. "It'll be interesting to see how Tyron does, but he has been drilling very well."
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