The Texas Longhorns have opened the first three practices to the media before opening three practices to the public on Thursday, Friday, and Saturday, so there are some early takeaways available from the Monday and Tuesday sessions.

The big news on Tuesday was that junior college transfer offensive tackle Desmond Harrison, who received some work with the first team on Monday, missed practice on Tuesday for reasons that were described to reporters on the scene as academic. He's expected to be back on Wednesday, but the missed practice means that those concerns about his eligibility have once again resurfaced. Given that he was able to impress observers through the first practice, Harrison was already living up to the significant expectations placed on him early.

Staying along the offensive line, senior offensive guard Trey Hopkins has been working at center, while senior offensive tackle Donald Hawkins moved in to play some guard on Monday when Harrison got reps with the first team at left tackle. It's an intriguing combination because Hopkins can match junior center Dominic Espinosa quickness and mobility at the second level, but he also doesn't have the issues against the pass rush that Espinosa continues to face ($) that are still limiting his upside through the first two practices.

Offensive line coach Stacy Searels likes to cross train his players, but this could be more than experimentation if Espinosa continues to struggle, especially if Harrison continues to come on and Hawkins performs well at guard, which may be his most natural position.

On the other side of the line of scrimmage, SA New-Express beat writer Mike Finger tabbed senior defensive end Reggie Wilson as one of the standouts from practice, calling him a "grown man" now. Wilson is in a major battle for playing time with junior Cedric Reed, who impressed late last season in the absence of senior Jackson Jeffcoat. Has the light finally come on for Wilson, who has always possessed the physical skills, but has never been able to consistently translate them to the football field? In any case, it's now or never for the recruit many had ranked above Jeffcoat coming out of high school.

Finger also mentioned that he's a fan of sophomore wide receiver Marcus Johnson, one of the young players who needs to step up during fall practice in the absence of senior Mike Davis and junior Jaxon Shipley as they recover from offseason injuries that aren't expected to keep them out of the opener against New Mexico State. Known as a strong route runner and hard worker, Johnson doesn't have the physical gifts of fellow sophomore Kendall Sanders in terms of speed, but he does have the potential to become a favored target for junior quarterback David Ash because of his reliability.

Ash had the following to say about Johnson on Monday:

Marcus has been making huge strides from where he was in the spring. I'm really excited just because with the nature of the offense and what we're doing now, he will have to be a big part of it. (He'll need to) make plays for us and have to be able to understand that when some of our primary receivers are covered or doubled, he's going to be the guy that gets the ball. I think he's doing a good job of getting prepared for that.

So what's the status of the defense through two days? Senior cornerback Carrington Byndom believes that there is a difference in this year's group:

I can tell it's the attitude. The attitude of the defense has changed. We took it upon ourselves to get some things corrected and become the defense that we wanted to be. We want to be a dominating defense. In these first two days, we've done that. We've come out and tried to prove a point.

Byndom spent some time working at safety with the Longhorns only trotting out four scholarship players there, a group that didn't include Kevin Vaccaro on Tuesday. Don't look for Byndom to see significant time at safety this fall, especially when junior Josh Turner returns from his injury (not to mention fellow junior Quandre Diggs), and too much was probably made of Diggs making a similar move last fall -- this is defensive back coach Duane Akina making sure that he has the versatility to survive injuries by cross training his players when possible. It also allows the players to more fully understand the defensive concepts in the secondary as a whole instead of only understanding their specific cornerback or safety role.

According to senior defensive tackle Chris Whaley, the changes in the Texas defense have started at the top with defensive coordinator Manny Diaz:

He is demanding more. Definitely demanding more out of us. It started in the bowl game. He came out a different way and just became more demanding. He is demanding the best and making sure that we come out every day with the mindset that we are going to dominate on defense.

Whaley specifically cited the aggressiveness of the defense as a big change from last season, though it would be better to hear him say that the linebackers have a better understanding of how to leverage opposing running backs and that Diaz has simplified his scheme to make sure that all the young players know where they need to be on every play.

Playing fast was something that the 2011 defense had to learn on the fly and was able to accomplish by the end of the season -- it's certainly an important part of adjusting to the fire zones that Diaz loves to run, which can be difficult for players to pick up because they have to know a number of adjustments that can get called at the line of scrimmage.

Perhaps defensive quality control assistant Greg Robinson can make a difference there, as he was at least at practice on Monday watching the team work.

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